'Talvisota' was the Finnish semi-official designation of the 'Winter War' between Finland and the USSR (30 November 1939/13 March 1940).

During the 'Talvisota', the Soviets were able to deploy more than three times as many men as the Finns: the Soviet strength rose from 425,500 men on 30 November 1939 to 760,600 men by the start of March 1940, while the total Finnish strength increased from 337,000 men on 30 November 1939 to 346,000 men at the beginning of March 1940.

The Soviet numerical superiority in armour was still greater, at about 100/1 at the beginning of the war the Soviets had 2,514 tanks and 718 armoured cars, and on the primary battlefield in the Karelian isthmus deployed 1,450 tanks; at the end of the war the Soviets had 6,541 tanks and 1,691 armoured cars. The Finns, on the other hand, had operated 32 French Renault tanks and few lighter tanks dating from 1919, but these were unsuitable for modern war and were generally used as fixed pillboxes; the Finns had also bought 32 British Vickers tanks during 1936/39, but without weapons that were to be manufactured and installed in Finland, but only 10 tanks were fit for combat at the beginning of the war.

The Soviet superiority in the air was in the order of 30/1.

This Soviet superiority in matériel was only part of the story, however, for the Finnish training and morale were excellent, while those of the Soviets had been very severely afflicted by Iosif Stalin’s vast purges of 1937/8. With more than 30,000 of its army officers executed or imprisoned, including most of those of the highest ranks, the Soviet army of 1939 had to rely on many inexperienced senior and middle rank officers. Because of these factors, and the combination of their high morale and experience in winter warfare, Finns were able to resist the Soviet invasion for a considerably longer period than the Soviets had expected in their worst prognostications. In 1809 the Russians had captured Finland from the Swedes, but Russo-Finnish relations, while never amicable, had become steadily worse after Russia unsuccessfully attempted a complete integration of Finland, hitherto a semi-autonomous grand duchy, into Russia. Starting late in the 19^th century, this effort completely soured Russo-Finnish relations and triggered steadily rising Finnish demands for full self-determination.

The start of World War I in 1914 and the collapse of the Russian empire in 1917 provided Finland with the opportunity her people wanted, and on 6 December 1917 the Finnish senate declared the independence of Finland. The new Bolshevik regime in Russia was weak and faced with the imminent threat of civil war, so Soviet Russia recognised the new Finnish government just three weeks after the declaration of independence. Sovereignty was achieved fully in May 1918 after a short civil war and the expulsion of Bolshevik troops. After the Soviet involvement in the Finnish Civil War in 1918, no formal peace treaty was signed. In 1918 and 1919, Finnish volunteer forces conducted two unsuccessful military incursions across the Russian border: the Viena and Aunus expeditions.

In 1920, Finnish communists based in the USSR tried unsuccessfully to kill General Carl G. E. Mannerheim, the former commander-in-chief of the Finnish White Guards. On 14 October 1920 the Russo-Finnish Treaty of Tartu confirmed the border between the two countries as the old border between the autonomous Grand Duchy of Finland and Imperial Russia proper and, additionally, Finland received the ice-free port of Petsamo on the Arctic Ocean. Even so, relations were still strained. The Finnish government allowed volunteers to cross the border to support the East Karelian Uprising in 1921, and Finnish communists in the USSR continued to prepare for a military return to Finland and undertook a cross-border raid, the so-called 'Pork mutiny', during 1922.

In 1932 the USSR and Finland signed a non-aggression pact, and this was renewed for a 10-year period in 1934. During the period in which Stalin was the ruler of the USSR, Soviet propaganda depicted the Finnish leadership as a 'vicious and reactionary Fascist clique'. Mannerheim and Väinö Tanner, the latter being the leader of the Finnish Social Democratic Party, were targeted for particular scorn. With Stalin attaining a position of almost absolute power as a result of the 'great purge', the USSR changed its policy toward Finland in the late 1930s within the context of a Soviet policy of pursuing the reconquest of the provinces of Tsarist Russia lost during the chaos of the October Revolution and the Russian Civil War. The Soviet leadership believed that the old empire had been ideally suited territorially for its own security, and wanted Leningrad (as Petrograd had been renamed) to enjoy a similar security. During April 1938, an NKVD agent, Boris Yartsyev, contacted Aimo Cajander and Rudolf Holsti, the Finnish prime minister and foreign minister respectively, to tell them that the USSR did not trust Germany and that war between the USSR and Germany was a possibility. Yartsyev added that the Soviet forces would not wait passively behind the USSR’s border but would rather 'advance to meet the enemy'. Finnish representatives assured Yartsyev that Finland was committed to a policy of neutrality and that the country would resist any armed incursion. Yartsyev suggested that Finland cede or lease some islands in the Gulf of Finland along the seaward approaches to Leningrad, but Finland refused this.

Negotiations continued fruitlessly throughout 1938, the Finnish reception of Soviet entreaties being decidedly cool in reflection of Finland’s lack of sympathy for the violent collectivisation and purges in the USSR. Moreover, most of the Finnish communist elite in the USSR had been executed during the 'great purge', further tarnishing the Soviet image in Finland. At the same time, Finland was trying to negotiate a military co-operation plan with Sweden, hoping for a joint defence of the Åland islands group in the mouth of the Gulf of Bothnia.

The USSR and Germany signed the Molotov-Ribbentrop Pact on 23 August 1939 and, while nominally a non-aggression treaty, this included a secret protocol whereby eastern Europe was divided into Soviet and German spheres of interest. Finland fell into the Soviet sphere. On 1 September 1939, Germany began its 'Weiss' (i) invasion of Poland, and two days later the UK and France declared war on Germany. On 17 September Soviet forces invaded and occupied eastern Poland. The Baltic states were later pressured to accept treaties allowing the USSR to establish military bases and to station troops on their soil: the Estonian government accepted the ultimatum, signing the relevant agreement in September, and Latvia and Lithuania followed in October.

Unlike the Baltic states, however, Finland started a gradual mobilisation under the guise of 'additional refresher training'. The Soviets had already started an intensive mobilisation near the Finnish border in 1938/39, but the assault troops for the invasion were not deployed until October 1939. Operational plans drafted in September called for the invasion to start in the following month.

On 5 October the USSR invited a Finnish delegation to Moscow for negotiations. Juho Kusti Paasikivi, the Finnish ambassador to Sweden, was sent to Moscow to represent the Finnish government. The Soviets demanded that the border between the USSR and Finland on the Karelian isthmus be moved to the west to a point only 18.5 miles (30 km) to the east of Viipuri and that the Finns destroy all existing fortifications on the Karelian isthmus. The Soviets also demanded the cession of islands in the Gulf of Finland and the Kalastajansaarento peninsula, and also the lease of the Hanko peninsula for 30 years so that the Soviets could establish a military base there. In exchange, the USSR would cede two municipalities with twice the territory demanded from Finland.

The major problem, so far as the Finns were concerned, was that acceptance of the Soviet demands would have forced them to dismantle their defences in Finnish Karelia. The Soviet offer divided the Finnish government, but this eventually rejected the Soviet ploy. On 31 October, in the assembly of the Supreme Soviet, foreign minister Vyacheslav Molotov made a public declaration of the Soviet demands. The Finns responded with a counter-offer whereby Finland would cede the Teri area, thereby doubling the distance between Leningrad and Finnish border, but by a distance still considerably shorter than the Soviets had demanded. The Soviets now deemed the time for negotiation to have ended.

On 26 November, a border incident was reported near the village of Mainila where, according to Soviet reports, a border guard post had been shelled by an unknown party resulting in the deaths of four border guards and injuries to another nine. (Later Soviet as well as Finnish research established that the shelling was carried out from the Soviet side of the frontier by an NKVD [Soviet internal security agency] unit with the express purpose of providing the USSR with a casus belli and the pretext required for the USSR to withdraw from the non-aggression pact.) At the time, Molotov claimed that the shelling was a Finnish artillery attack and demanded that Finland apologise for the incident and move its forces beyond a line 12 to 16 miles (20 to 25 km) behind the frontier. Finland denied responsibility for the attack, rejected the demands, and called for a joint Finnish and Soviet commission to examine the incident. Claiming that the Finnish response was hostile, the USSR next renounced the non-aggression pact on 28 November.

On 30 November the Soviets invaded Finland with a force of 21 divisions, totalling some 450,000 men, and also bombed Helsinki. Mannerheim was appointed commander-in-chief of the Finnish forces immediately after the Soviet attack, and the government was reshuffled with Risto Ryti as the new prime minister and Väinö Tanner as the foreign minister. On 1 December the Soviets created a puppet government, under Otto Wilhelm Kuusinen, intended to rule Finland after its anticipated defeat and the creation of the Finnish Democratic Republic. The puppet government was also dubbed the 'Teri government' after the village of Terijoki, the first place the advancing Soviet forces captured.

The Soviets expected to secure total victory over the Finns in a matter of weeks. The Soviets forces had just completed their invasion and seizure of eastern Poland at a cost of less than 1,000 casualties. While Stalin’s expectations of a quick victory were backed a number of senior communist party members and Marshal Sovetskogo Soyuza Kliment E. Voroshilov, the defence minister, other senior officers had major misgivings about the undertaking. The army chief-of-staff, Komandarm 1 ranga Boris M. Shaposhnikov, had prepared an alternative invasion plan based on a major build-up, extensive logistical and fire support preparations, and a rational order of battle deploying the army’s best formastions. The military commander selected by Andrei A. Zhdanov, the chairman of the Supreme Soviet, Komandarm 2 ranga Kirill A. Meretskov, whose Leningrad Military District (Leningrad Front after the start of hostilities) was to supervise the Soviet undertaking, reported at the start of the hostilities that 'The terrain of coming operations is split by lakes, rivers, swamps, and is almost entirely covered by forests… The proper use of our forces will be difficult.' However, these doubts were not reflected in his troop deployments, and Meretskov announced publicly that the Finnish campaign would take at the most two weeks: Soviet soldiers had even been warned not to cross the border into Sweden by mistake after driving straight across Finland.

However, Stalin’s purges had devastated the Soviet officer corps: those purged included three of its five marshals, 220 of its 264 army, corps and divisional commanders, and 36,761 officers of all ranks. Fewer than half of the pre-purge officers remained, and command situation was exacerbated by the fact that the purged officers of all levels were generally replaced by men who were less competent but deemed to be either more loyal or more pliable. Furthermore, formation and unit commanders were paralleled by political commissars, who could chose to ratify or deny military decisions on their political merits, further complicating the Soviet chain of command. This system of dual command effectively destroyed the independence of commanding officers and completely removed their chances of displaying initiative.

After the undeclared border clashes between the USSR and Japan in Manchuria, culminating on the decisive Soviet victory in the Battles of Khalkin Gol between 11 May and 16 September 1939, the Soviet high command had divided into two factions. One side was represented by Spanish Civil War veterans such as the air force’s Komandarm 2 ranga Pavel V. Rychagov, the armoured force’s Komandarm 1 ranga Dmitri G. Pavlov, and Stalin’s favourite general, Marshal Sovetskogo Soyuza Grigori I. Kulik, the head of the artillery arm. The other side was led by Khalkin Gol veterans such as the army’s Komandarm 2 ranga Georgi K. Zhukov and the air force’s Komandarm 2 ranga Grigori P. Kravchenko. Under this divided command structure, the lessons of the USSR’s first large-scale campaign based on the integration of armour, artillery, infantry and aircraft at Khalkin Gol were largely ignored by the ascendant Spanish Civil War faction.

As a result, in the 'Talvisota' winter war the Soviet use of armour was woefully deficient at the tactical and operational levels, and it took the USSR three months and more than one million men to do what Zhukov had achieved in the final Battle of Nomonhan in just the last 11 days of August 1939.

The majority of Soviet generals had been highly impressed by the success of the Germans' interim form of Blitzkrieg (lightning war) tactics in 'Weiss' (i). However, these tactics had been schemed on the basis of central European geographical conditions with a dense, well-mapped network of paved roads to provide the logistic support required by the fast-moving armoured forces. Armies fighting in central Europe had recognised supply and communications centres, which could be easily targeted by armoured units and formations.

The bases serving the Finnish forces were somewhat different inasmuch as they were located deep inside the country. There were no paved roads, and even gravel or dirt roads were scarce; most of the terrain consisted of trackless forests and swamps. Waging a Blitzkrieg campaign in Finland was therefore a highly difficult proposition, and the Soviet forces failed to meet the level of tactical co-ordination and local initiative required to execute Blitzkrieg tactics in the Finnish theatre.

At the start of the 'Talvisota' winter war, the Soviet ground forces were positioned in three groupings. In the extreme south Komandarm 2 ranga Vsevolod F. Yakovlev’s (later Meretskov’s) 7^th Army, comprising two infantry corps (nine divisions), one tank corps and three tank brigades, was located on the Karelian isthmus, and had as its task a north-western advance to take the city of Viipuri (Vyborg in Russian); the 7^th Army was later divided to create a revised 7^th Army and a 13^th Army. To the north of Lake Ladoga was Komandarm 2 ranga Ivan N. Khabarov’s (from 13 December Komandarm 1 ranga Grigori M. Shtern’s) 8^th Army, comprising six divisions and one tank brigade, and this had as its mission the execution of a flanking movement to the west round the northern shore of Lake Ladoga before wheeling to the south-west to strike at the rear of the 'Mannerheim-linja' (Mannerheim Line). Still farther to the north, in the area to the west of the White Sea, was Komkorps Mikhail P. Dukhanov’s 9^th Army with two corps (four divisions with a fifth on its way) positioned to strike to the west into central Finland and cut Finland in half. In the far north, Komandarm 2 ranga Valerian A. Frolov’s 14^th Army (three divisions) was based in Murmansk with the task of seizing Petsamo and then wheeling to the south-west to take Rovaniemi.

To counter these three main Soviet thrusts, the Finns had developed a strategy driven largely by their very considerably inferior numbers and the particular nature of their country’s eastern regions. The frontier with the USSR was more than 620 miles (1000 km) long but was generally impassable except along a handful of unpaved roads. In pre-war calculations, the Finnish general staff, which established its wartime headquarters at Mikkeli, estimated the Soviet strength as seven divisions on the Karelian isthmus and no more than five along the whole frontier to the north of Lake Ladoga, and therefore reckoned that the Soviets would possess a manpower superiority of 3/1. The actual ratio was somewhat greater in the Soviets' favour: for example, 12 Soviet divisions were deployed in the area to the north of Lake Ladoga.

An even greater problem for the Finns than their shortage of manpower was their paucity of matériel. Imports of anti-tank weapons and aircraft were arriving, but only in small quantities; and the ammunition situation was alarming, as the Finnish stockpiles had small arms ammunition, artillery ammunition and fuel for only 19 to 60 days of operations. The ammunition shortage meant the Finns could seldom afford counter-battery or saturation fire. At a mere 32 vehicles, of which only 10 were operational as noted above, the Finnish armoured strength was operationally nonexistent.

Like those of the Soviets, the Finnish forces were deployed in three groups. Kenraaliluutnantii Hugo Viktor Österman’s Kannaksen Armeija (Army of the Isthmus) comprised six divisions within Kenraaliluutnantti Harald Öhquist’s II Armeijakunta (corps) and Kenraaliluutnantti Axel Erik Heinrichs’s III Armeikakunta on its right and flanks respectively with the corps boundary extending along the Vuoksi river. Kenraalimajuri Kaarlo Aleksanteri Heiskanen’s (soon Kenraalimajuri Johan Woldemar Hägglund’s) IV Armeijajunta (two divisions and a group of three brigades) was located to the north of Lake Ladoga. Kenraalimajuri Viljo Einar Tuompu’s Pohjois-Suomen Ryhmä (North Finland Group) was a collection of civic guards, border guards and drafted reservist units, and was tasked with the defence of Finland to the north of the IV Armeijakunta.

The Finns could call on only 114 operational aircraft, whereas the Soviets a very considerably larger but unrevealed number of warplanes.

The main weight of the Soviet offensive was directed to the north-west though the Karelian isthmus held by the Kannaksen Armeija occupying the fixed defences of the 'Mannerheim-linja'. This line, comprising a complex of defensive elements, was located on the Karelian isthmus about 19 to 47 miles (30 to 75 km) from the Soviet border, and took the form of four main elements. That immediately in front of the Soviets was the Pääasento (Main Position) between the Gulf of Finland in the south-west and the Vuoksi river in the north-east via the Muolaanjärvi lake: this line was held, from right to left, by the 4^th, 3^rd, 1^st and 2^nd Divisioonat (divisions) with the 5^th Divisioona in reserve just forward of the Väliasento (Intermediate Position). Just behind the Pääasento, between Summa and the Muolaanjärvi lake, was the shorter Summa-Sektori (Summa Sector). Farther to the rear, between the Bay of Viipuri and the Vuoksi river just to the south-east of Vuosalmi, on an almost west/east line, was the Väliasento. Finally, covering the area between Viipuri in the west and Vuosalmi in the east, was the Taka-Asento (Rear Position) held by the 23^rd and 21^st Divisioonat on the right and left respectively. The northern bank of the Suvanto waterway of the Vuoksi river’s lower reaches between Taipale on Lake Ladoga and Vuosalmi at the virtual junction of the Intermediate and Rear Positions was held against the possibility of a Soviet outflanking attack over the frozen water by the 7^th and 8^th Divisioonat of the III Armeijakunta.

In the Karelian isthmus the Soviets had mustered some 250,000 men facing about 130,000 Finns including a covering force of about 21,000 men in the area ahead of the 'Mannerheim-linja' to delay and inflict losses on the Soviet forces before they reached the line. At the tactical level the greatest threat to the Finns was posed by the Soviet armour, for the Finns possessed only small numbers of anti-tank weapons and lacked adequate training in modern anti-tank tactics. This threat was mitigated, however, by the fact that the favoured Soviet armoured tactic was a simple frontal charge, and this was a weaknesses the Finns were quick to appreciate and exploit. The Finns rapidly learned that at close range tanks could be tackled in several ways: for example, logs or crowbars jammed into the bogie wheels often served to immobilise a tank. The Finns were soon able to field a better extemporised weapon in the form of the so-called 'Molotov cocktail', which was a glass bottle part-filled with flammable liquid and fitted with a simple hand-lit fuse. Molotov cocktails were eventually mass-produced in Finland by the Alko corporation and delivered in bundles together with the matches with which to light them. Some 80 Soviet tanks were destroyed in the fighting in the frontier zone.

By 6 December all the Finnish covering forces had withdrawn to the Main Position. The Soviets launched their first major attack against the Finnish defences in the Taipale area between the western shore of Lake Ladoga, the Taipale river and the Suvanto waterway. Along the Suvanto sector, the Finns had the slight advantage of higher ground which was sufficiently dry to allow entrenched defences. Anticipating a Soviet assault in this area, the Finnish artillery had reconnoitred the area and developed fire plans in advance.

The Battle of Taipale between 6 and 27 December began with a 40-hour Soviet artillery preparation. After the barrage, the infantry of Komdiv Vladimir D. Grendal’s so-called Right-Wing Group attacked in divisional strength across open ground on 3 December, but was repulsed with heavy casualties. Between 6 and 12 December the Soviets continued their effort in this sector using only one division, but their continued lack of success then led them to strengthen their artillery support, bring up armour and reinforce the Right-Wing Group with the 10^th Division. On 14 December, the bolstered Soviet forces launched a new attack on the Taipale sector, but were once again repulsed. A third Soviet division was then committed, but performed poorly and panicked under artillery fire. The Soviets assaults continued without success, and the Soviets suffered heavy losses: a typical Soviet attack during the Battle of Taipale lasted just one hour and left 1,000 dead and 27 knocked-out tanks on the ice.

Another engagement in the same general area was the Battle of Kelja on 25/27 December. In the weeks before the start of the fighting, the whole of the Taipale area had been subjected to heavy artillery fire and daily infantry attacks, the latter being repulsed mainly by Finnish artillery. The infantry attacks had reached their climax on 17 December, but ended abruptly on the next day even as the artillery bombardment increased in intensity. In the last few days before the main attack, Finnish reconnaissance aircraft reported the arrival of the Soviet 4^th Division, and ground patrols reported unusually high numbers of Soviet troops in the area.

The Soviet attack began early in the morning on 25 December, with Soviet soldiers crossing the iced-over Suvanto lake under the cover of darkness. Covered by a heavy fall of snow, the attack achieved almost complete surprise. The Soviets unleashed a massive artillery barrage on the Patoniemi fortress, away from the main attack at Kelja. When the first Soviet soldiers reached the Finnish line, artillery finally opened on Finns' forward positions. This caused confusion among the Finns about the scale of the attack.

Soon three 'beach-head' areas were secured by the Soviets at Patoniemi, Volossula and Kelja. Finnish artillery was able to repel the second and third waves of reinforcements, but a battalion had already landed at each of the three 'beach-heads'.

On the Patoniemi sector, the Soviets had deployed their heavy machine guns on the flanks of the Finnish positions before they realised what was happening. The defenders were able to stall the attack long enough to alert their battalion headquarters. Finnish command reacted swiftly, committing a reserve battalion to the defence, and within a few hours the majority of the attackers had been pushed back across the ice or destroyed. However, sporadic resistance lasted until evening, when the area was finally cleared.

The Volossula sector was put on alert following the local commander’s receipt of information about the Patoniemi landing. After reporting that there were no Soviet forces in sight, the commander was ordered to advance his men toward Patoniemi, but then Soviet troops began to land and the Volosulla force was compelled to handle this before advancing. The Finnish battalion sent to reinforce the company defending the beach was struck by artillery fire, but managed to reach its objective within an hour. When the battalion arrived, the Soviets had already begun to entrench themselves, and fierce combat followed before the Soviets were driven back across the ice with heavy casualties.

In the Kelja sector, the battalion commander received reports of Soviet forces crossing the ice. Finnish artillery immediately fired on the Soviets and prevented their left wing from reaching the shore. By the time the battalion reserves could be mobilised, the rest of the attacking forces were already near Kelja. A Finnish counterattack managed to push the Soviets back to the edge of the forest with the help of an artillery barrage, but here the Soviet troops dug in and managed to repel another counterattack in fighting which lasted throughout the day.

Throughout 26 December, the Soviets tried to send across the ice reinforcements. most of whom were repulsed by the Finnish artillery. Two more counterattacks against the entrenched Soviet positions failed as the situation became more serious. The Finnish command decided that an immediate and decisive counterattack was needed to stabilise the situation. Early in the morning of 26 December, therefore, the Finnish attack began as a single company advanced. Without the artillery and the mortars the attacking force had been promised, and also under heavy Soviet fire, the Finns were forced to retreat.

Another attack, this time with two companies, began later that day. The attack made some early gains, but after using most of their ammunition and coming under a heavy artillery bombardment, the Finns were also forced to withdraw. The rest of the battalion was ordered to hold its positions and prevent Soviet reinforcements from crossing the ice.

Throughout the night, the 4^th Division made repeated attempts to reinforce their positions on the shore, but because of the clear moonlight, all of these attempts were repulsed by the Finnish artillery. Nearly a complete regiment took part in these attacks, which were disastrous.

On 27 December, the Finns launched yet another counterattack after the Soviets had received an artillery bombardment. This attack failed in the face of heavy machine gun fire, and the Finns were forced to withdraw once again.

Then, later on the same day, the Finns made another counterattack, this time with greater artillery support. This was a success, as the battered Finnish company managed to infiltrate Soviet positions. After over seven hours of continuous fighting, the majority of Soviet resistance collapsed, though with a high cost. By the morning of 28 December, the area had been wholly cleared, and the Battle of Kelja was over.

Although the Soviet attack eventually failed, it did succeed in draining the Finns' Taipale sector of reserves. The Finns were so short of men that reserves from the western end of the Karelian isthmus had to be relocated to Taipale, further weakening the western area. The Soviets lost about 2,000 men killed and the Finns 141 men killed and 375 wounded, but did capture a quantity of much-needed equipment from the Soviets. This booty included 12 anti-tank guns, 140 machine guns, 200 light machine guns and 1,500 rifles.

To the north of Lake Ladoga, on the Ladoga Karelia front, the defending Finnish units relied on the terrain rather than fortifications, all the more so as this large forest wilderness lacked any road network which the Soviets might otherwise have used to prepare, launch and support a major operation. However, the 8^th Army had extended a new railway line to the border and was thus able to double the supply capability on the front, leading to major operations on the Ladoga Karelia front. In central and northern Finland, roads were few and the terrain hostile. The Finns did not expect large-scale Soviet attacks, but here the Soviets committed eight divisions, strongly supported by armour and artillery. The 155^th Division attacked toward Lieksa, and farther still to the north the 44^th Division attacked at Kuhmo as it tried to reach Suomussalmi. The 163^rd Division was deployed at Suomussalmi and charged with cutting Finland in half by advancing along the Raate Road to reach the Gulf of Bothnia at Oulu.

The Battle of Suomussalmi was fought between 7 December 1939 and 8 January 1940, and pitted three Finnish regiments and a number of separate battalions, numbering about 11,000 men under the command of Eversti Hjalmar Fridolf Siilasvuo, against two divisions and one tank brigade of the 9^th Army, numbering between 45,000 and 55,000 men under the command of Komdiv Ivan F. Dashichev. The battle resulted from the first Soviet advances on centre of the front, starting on 30 November as Komdiv Andrei I. Zelentsov’s 163^rd Division crossed the frontier and advanced toward the key settlement of Suomussalmi with the objective of driving as far to the west as the city of Oulu, on the east coast of the Gulf of Bothnia, and thereby effectively cutting Finland in half.

This sector was defended by only one Finnish unit (Er. P 15, or 15^th Detached Battalion), positioned near Raate, to the south-east of Suomussalmi. With the main strength of the 163^rd Division advancing to the west and then south-west, the 759^th Regiment farther to the south attacked to the west and then to the north-west, the Soviet plan being that these two elements should meet in Suomussalmi. The main body of the 163^rd Division reached Palovaara, to the north of Suomussalmi, on 4 December, and there divided with the 662^nd Regiment driving to the north to take Piispajärvi lake on 6 December and the 81^st Regiment to the south in the direction of Suomussalmi. The 759^th Regiment and 81^st Regiment reached Suomussalmi on 7/8 December, and took the settlement against only minimal resistance as the Finnish covering forces comprised only two incomplete companies with which to undertake an inevitably unsuccessful holding action between the border and Suomussalmi, but the Finns destroyed the settlement before the Soviet arrival to deny the Soviets shelter, and withdrew to the opposite shore of the Niskanselkä and Haukiperä lakes.

The first extensive fight started on 8 December, when Soviet forces began to attack to the west across the frozen lakes. This attempt failed completely. The second part of the Soviet force led the attack to the north-west on Puolanka, which was defended by the newly arrived Er. P 16, and this Soviet attempt also failed. On 9 December, the defenders were reinforced by the 27^th Jalkaväkirykmentti (infantry regiment), a newly raised infantry unit, and Siilasvuo was appointed to the command of the Finnish forces in this key area.

Siilasvuo immediate began an effort to regain Suomussalmi. The main Finnish force advanced on Suomussalmi, but failed to take the village and in the process sustained major losses. On 24 December the Soviets counterattacked, but failed to break through the surrounding Finnish forces. Reinforced by two new regiments (the 64^th and 65^th Jalkaväkirykmentit), the Finns again attacked on 27 December, and this time took the ruined settlement. The Soviets retreated in disarray over the ice of the surrounding frozen lakes.

The Battle of Suomussalmi and the associated Battle of the Raate Road constituted a major victory for the Finns. If the Soviets had been able to press forward and capture Oulu, the Finns would have had to defend the country on two fronts and an important railway link to Sweden would have been severed. The battle also gave a decisive boost to the morale of the Finnish army.

Finnish losses were in the order of 750 men killed or missing, and 1,000 wounded, whereas those of the Soviets were between 13,000 and 23,000 men killed, wounded and missing, 2,100 men taken prisoner, 43 tanks captured, 71 field guns captured, 29 anti-tank guns captured, 260 trucks captured, and 1,170 horses captured.

The Battle of Suomussalmi is often cited as an example how a small force, properly led and fighting in familiar terrain, can defeat a vastly numerically superior opponent. Among the many factors which contributed to the Finnish victory were the Finns' superior mobility through the use of skis and sledges to allow cross-country movement against Soviet elements whose heavy equipment confined them to roads; the Finns' flexible and often unorthodox tactics, such as the targeting of Soviet field kitchens, which demoralised Soviet soldiers fighting in a sub-Arctic winter; the poor state of the Soviet forces' equipment, especially with regard to their use of inappropriate camouflaged winter clothing; the failure of Soviet counter-intelligence, which meant that the Finns were often able to intercept Soviet communications, which relied heavily on standard phone lines; the greater suitability of Finnish equipment for operations in deep snow and freezing temperatures; the basic improbability of the Soviet attempt to cut Finland in half as while this objective appeared feasible on paper, it was practically unrealistic as the region was mostly forested marshland with its road network consisting mainly of logging trails, where mechanised forces became easy targets for the mobile Finnish ski troops; and the Finnish forces' use of the simplest possible tactics, which decreased the chances of tactical errors and accorded well with the overall effects of the adverse weather.

Fought within the context of the Battle of Suomussalmi, the smaller Battle of the Raate Road between 1 and 7 January pitted an initial force of about 6,000 Finns rising during the course of the fighting to about 10,000 against between Soviet forces estimated at between 13,960 and 25,000 men. On 7 December the 163^rd Division had captured Suomussalmi, but almost immediately found itself trapped deep inside Finnish territory, so the 44^th Division was sent to its aid via the Raate Road linking Latvajärvi in the USSR with Suomussalmi. Realising that the junction of the two Soviet divisions would make it impossible for his smaller Finnish forces to prevail, Siilasvuo managed to check and then decisively defeat the Soviet forces on the Raate Road in a battle that further emphasised the effectiveness of the Finnish motti tactics of breaking Soviet formations into separate and this smaller groups that could then be encircled and destroyed on a piecemeal basis. During the Battle of Suomussalmi, the Finns cut the Raate Road on 11 December, thereby severing the second, southern supply route to the 163^rd Division in Suomussalmi. The Finns also cut the first, northern supply route on 13 December, and the Soviets were forced to open a new supply route over the ice of the Kiantajärvi lake.

The 163^rd Division was nearly surrounded in Suomussalmi and suffering major casualties as the Soviet situation worsened, and on 20 December Komdiv Andrei I. Zelentsov, commander of the 163^rd Division, sought authorisation to fall back from Suomussalmi. In response, part of the 44^th Division, the 1/305^th Regiment and the 3/662^nd Regiment were sent to reinforce the 163^rd Division near Suomussalmi. Zelentsov’s concerns were not understood by the Soviet higher command echelons as the entire 44^th Division was about to move along the Raate Road.

This road was in fact a battlefield throughout the 'Talvisota' winter war, but the Battle of the Raate Road was fought on 1/7 January. Before their main battle against the 44^th Division, the Finns had fought a defensive battle against part of 163^rd Division on the Raate Road, and after the Battle of the Raate Road more fighting took place just to the eastern side of the frontier on the same road.

At the start of the Battle of the Raate Road, what was now Siilasvuo’s 9^th Divisioona had already effectively destroyed the 163^rd Division. After that it was ordered to destroy the 44^th Division, which was halted on the road near Haukila, 7.5 miles (12 km) to the east of Suomussalmi. Siilasvuo divided the 9^th Divisioona into four groups named after their commanders, and ordered these to launch their attacks at 08.30 on 5 January. The fighting was centred on Haukila, where most of the Soviet troops were located and where the 'Mandelin' Ryhmä and 'Mäkiniemi' Ryhmä were based. The 'Mäkiniemi' Ryhmä had started moving on Haukila a few days before the attack was scheduled, and at the same time the fresh 3^rd NKVD Border Guard Regiment was just arriving to assist the 44^th Division. By the following morning, the Finnish troops held strong blocking positions reinforced by minefields at several points in the middle of the extended Soviet column. On 6 January there was heavy fighting all along the Raate road as the Finns continued to break the Soviet force into small elements. The Soviets tried to overrun the Finnish roadblocks with armour, but lost many tanks in frontal attacks and were unsuccessful. Finally, at 21.30, Vinogradov ordered his division to fall back to the Soviet border. The Soviet troops began to escape to the north over the Kiantajärvi lake, but many of the men froze to death as they lacked proper clothing and food. Some Soviet remnants had already tried to escape to the east, but were blocked by the 'Kari' Ryhmä. Farther in the east, the 'Fagernäs' Ryhmä was not strong enough at first to hold a strategic bridge, but on 7 January recaptured the bridge and before 12.00 all organised Soviet resistance had ended. Mopping-up operations lasted two days, during which the Finns rounded up hundreds of Ukrainians. Other remnants of the 44^th Division managed to escape the blockade and reach the border in several small groups.

Among the large quantity of matériel which the Finns captured, with the Soviet admitted loses in parentheses, were 4,822 (4,822) rifles, 106 (97) machine guns, 190 (252) light machine guns, 71 (55) pieces of artillery, 29 (30) anti-tank guns, 14 (12) anti-tank rifles, 43 (37) tanks, 10 armoured cars, 260 trucks, 20 artillery tractors, two cars and 1,170 horses. Most of this equipment was quickly absorbed into service with the Finnish army.

There has long been dispute about the casualty figures. For many years Finnish historians estimated the Soviet losses as about 17,000 men killed in addition to 1,300 men taken prisoner, this estimate being based on the interrogation of prisoners of war including officers of the 27^th Regiment who had said their losses were in the order of 70% of what the Finns assumed was a 44^th Division strength of more than 20,000 men. The Soviets challenged this casualty estimate, and in January 1940 claimed to have lost no more than 900 men, mostly from frostbite, while inflicting an estimated 2,000 deaths on the Finns. whose actual losses were in the order of 1,200 killed. Later Finnish historians conducted further efforts to ascertain the number of Soviet casualties, and the most recent Finnish studies suggest a Soviet toll of at least 7,000 to 9,000 men.

To reduce the possibility of an epidemic, the Finns buried the Soviet dead as the weather warmed during the early spring. Mass graves were marked on maps, which later disappeared, and marked these with a cross or a pole. At about Easter 1940, the Soviets indicated their desire to gather and repatriate the dead, but while they refused to allow Soviet officials to cross the border the Finns delivered 300 bodies from area of Raate village to Soviet officials. By the time the 'Jatkosota' continuation war ended in September 1944, the Soviets were no longer interested in their dead. The Soviets occupied the Raate road area for a short time, gathered wartime debris, but left the bodies alone as the Raate road disaster had by then become a 'non-event'.

Vinogradov and two of his chief officers had pulled back during critical fighting and thereby, according to the Stavka, undermined the morale of the 44^th Division. When they reached the Soviet lines four days later, the three men were court-martialled, found guilty and sentenced to death, the sentences being carried out immediately.

Somewhat farther to the north, in Finnish Lapland, the 88^th Division and 122^nd Division attacked toward Salla in Lapland, and the 104^th Mountain Division attacked the Arctic port of Petsamo by sea and land with the support of naval gunfire.

Naval operations in the Gulf of Finland included 'Fakel' as the Soviets took the Seiskari and Lavansaari islands off the Finnish coast, commanding the approaches to Leningrad, but failed in amphibious operations to take the ports of Porvoo, Hanko and Turku on Finland’s south coast, the first to the east of Helsinki and the other two to the west of the Finnish capital.

Throughout these operations, the weather was one of several decisive factors. The winter of 1939/40 was exceptionally cold. At the start of hostilities, only those Finnish soldiers on active service had uniforms and weapons, while all the rest had to make do with their own clothing, which for many soldiers was their normal winter clothing with the semblance of an insignia added. The Finnish soldiers also used their own skis, and were very skilled in cross-country ski movement. The combination of extreme cold, snow, forested terrain and the long hours of darkness were in combination a geographical and climatic factor which the Finns could turn to their advantage. The Finns dressed in layers, and the ski troopers wore a lightweight white snow cape, which rendered them almost invisible as they executed guerrilla attacks against Soviet columns. At the beginning of the war, Soviet tanks were painted in standard olive drab and the men were dressed in standard khaki uniforms, and it was not until a time late in January 1940 that the Soviets painted their equipment white and issue snowsuits to their infantry. Most Soviet soldiers had proper winter clothes, but this was not the case with every unit. In the Battle of Suomussalmi, many Soviet soldiers died of frostbite. The Soviet troops lacked skill in skiing, so soldiers were restricted to movement by road and were forced to move in long columns. Furthermore, the Soviet forces lacked winter tents in adequate qualities and quantities, so most men had to sleep in improvised shelters. In Soviet field hospitals, operations were undertaken in temperatures as low as -20° C (-4° F) while outside the canvas tent wall the temperature was -30°C (-22° F).

On the other side of the front line, however, injured Finnish soldiers could expect a heated operating room. Some Soviet units suffered frostbite casualties as high as 10% even before crossing the Finnish border. However, the one advantage that the bitter cold did confer on the Soviets was the consolidation of marshes, swamps and water surfaces, which made it possible for their armour to move off the roads.

In the fighting from Karelia to Finland’s Arctic coast on the Barents Sea, the Finns made extensive use of guerrilla tactics. The Soviets had the advantage of superior numbers and materiel, but the Finns offset this notional superiority through the use of speed, tactics and economy of force. Particularly on the Karelia Ladoga front and during the Battle of the Raate Road, the Finns broke up larger Soviet formations into small units which they then surrounded and destroyed.

The terrain of the Karelian isthmus was not conducive to the use of guerrilla tactics, however, so the Finns had perforce to rely on the fixed defences of the 'Mannerheim-linja', whose flanks were protected in the south-west by the Gulf of Finland and in the north-east by Lake Ladoga, though both of these were frozen during the winter months. The Finns had built 221 strongpoints across the Karelian Isthmus, most of them during the early 1920s, but many of these were extended in the late 1930s. Despite these defensive preparations, even the most heavily fortified section of the 'Mannerheim-linja' had only one reinforced concrete bunker every 1 km (0.6 mile). In overall terms the line was weaker than similar lines in continental Europe.

On the north-eastern end of the Karelian isthmus, the Soviet forces had attempted to break through, or rather to outflank, the 'Mannerheim-linja' in the Battle of Taipale. Toward the south-western end of the line, the Soviets faced the Finnish line at Summa, near the city of Viipuri, on 16 December. The Finnish defence in the Summa sector, where the village of that name lay on the road linking Leningrad and Viipuri, was centred on a complex of 41 reinforced concrete bunkers, making the line in this area stronger than anywhere else on the Karelian isthmus. However, because of an error in the planning, the nearby Munasuo swamp was the site of a gap, some 0.6 mile (1 km) wide, in the line.

During the 1^st Battle of Summa, about 20 Soviet tanks broke through the thin line of this on 19 December, but the Soviets failed to benefit from this limited breakthrough as a result of non-existent co-operation between their different branches of their forces. Lacking anti-tank weapons adequate for the task of knocking out this armour, the Finns remained in their trenches, allowing the Soviet tanks to move freely behind the Finnish line, but nonetheless succeeded in repelling the main Soviet infantry assault. The tanks, stranded behind the Finnish lines, attacked strongpoints at random until they were all eventually destroyed. By 22 December, the battle had ended in a Finnish victory.

The Soviet advance was stopped along the 'Mannerheim-linja', the Finnish success being attributable as much to the Soviet forces' poor morale and shortage of supplies as to the Finnish success it driving back what were in general suicidal frontal attacks. Öhquist then decided on a counterattack to encircle three Soviet divisions into a motti near Viipuri on 23 December, but the plan was overly ambitious and failed. The Finns lost 1,300 men, and the Soviets were later estimated to have lost a similar number.

At the other end of the Karelian front, in the Ladoga Karelia region to the north of Lake Ladoga, the 8^th Army committed its 168^th Division, 18^th Division, 56^th Division, 75^th Division, 139^th Division and 155^th Division, from south to north, in convergent attacks to the west into Finland, but was checked on 12 December after an advance of dozens of miles at Tolvajärvi (139^th Division), Kollaa (56^th Division) and between Impilahti and Saarijärvi (168^th Division and 18^th Division), and then almost surrounded near the northern shore of Lake Ladoga. The strength of the Soviet onslaught to the cnorth of Lake Ladoga came as an unwelcome surprise to the Finnish high command, for the area was held by only two Finnish formations, namely Eversti Lauri Tiainen 's 12^th Divisioona and Eversti Hannu Esa Hannuksela’s 13^th Divisioona. The two divisions were supported by a group of three brigades, bringing the Finns' local strength to more than 30,000 men. The Soviets deployed a division for almost every road leading to the west across the Finnish border.

Commanded by Khabarov, who was replaced by Shtern on 13 December, the 8^th Army had as its mission, to be completed within 10 days, the destruction of the Finnish troops in Ladoga Karelia and the advance into the area between Sortavala and Joensuu. The Soviets had a 3/1 advantage in manpower, 5/1 advantage in artillery, and total air supremacy. The Finnish forces initially panicked and retreated in front of the overwhelming strength, and and an early consequence was the replacement of Heiskanen as commander of the IV Armeijakunta by Hägglund on 4 December. On 7 December, in the middle of the Ladoga Karelian front, Finnish units retreated near the small stream of Kollaa. The water course was too small to offer protection by itself, but was flanked by banks up to 33 ft (10 m) high, and it was here in the centre of the Ladoga Karelia front that the Battle of Kollaa was fought from 7 December right to the end of the 'Talvisota' winter war on 13 March 1940.

Despite their numerical inferiority to their Soviet opponents, the men of the 12^th Division were able to repel Komdiv Mikhail S. Evstigneyev’s 56^th Division because the Soviets were prepared, or only able, to move along the roads. The area possessed very few roads, all of them held by Finnish troops, and the Soviets were not able to proceed across country without skis. Kollaa is often considered to have been one of the most difficult places to defend during the 'Talvisota' winter war. It has been estimated that the Soviets fired almost 40,000 artillery rounds at the defence line during a single day, whereas the Finnish artillery could respond with a maximum of 1,000 rounds per day at the very most. Although the 12^th Divisioona did succeed in its task of halting the 56^th Division in fighting which cost each side very heavily, essentially static warfare continued into March 1940, by which time the Soviets had committed four divisions and one tank brigade as the XIV Corps under the command of Kozlov and then Komdiv Vasili G. Vorontsov. The Soviets managed to penetrate the Finnish defence line at Kollaa on several occasions, thus pushing the Finns out of their positions, but the Finns counterattacked to restore their positions. Yet the Finnish defence was close to collapse at the very end of the war: one day before the end of hostilities, the Soviets managed to drive a salient, between 550 and 1,650 yards (500 and 1500 m) deep, into the Finnish defences. As a result Kenraalimajuri Antero Johannes Svenson, who had succeeded to command of the 12^th Divisioona on 31 January after Tiainen had fallen ill, considered abandoning the line at Kollaa, but as reports from the sector were that the situation was 'not yet that alarming', he ordered a counterattack to restore the Finnish position on the following day. However, as the information of the peace treaty reached the front, this order was cancelled and the Finns were told to hold their current positions until the end of hostilities, by which time the battle had cost the Finns some 1,500 dead and wounded, and the Soviets an estimated 8,000 dead and wounded.

In the northern sector of the Ladoga Karelia front, meanwhile, the Finns had retreated from the Ägläjärvi lake to the Tolvajärvi lake on 5 December and then repelled a Soviet offensive in the Battle of Tolvajärvi on 11/12 December. The Finnish forces on the Ladoga Karelia front had started to fall back, in the face of the Soviets' considerable numerical and matériel superiority, as soon as the war began on 30 November. The Finns had not believed that the Soviets would be not be able to deploy large number of troops in this rugged and almost roadless area, but the Soviets in fact committed one division and a tank brigade with another division following. But on 12 December, Komdiv Nikolai I. Beliayev’s advancing 139^th Division, supported by the 56^th Division, was defeated by a much smaller Finnish force of 4,000 men under Eversti Paavo Juho Talvela in the Battle of Tolvajärvi on 12 December, the first Finnish victory of the war. After the start of the Soviet offensive, the Finnish forces to the north of Lake Ladoga had begun a pre-planned retreat in the face of an attack in overwhelming strength. It was not thought possible for the Soviets to deploy large number of troops in this rugged and almost roadless area, but the Soviets deployed the whole of 139^th Division (718^th, 609^th and 364^th Regiments) and a tank brigade, which advanced along the road between the Suojärvi and Tolvajärvi lakes, and thus posed a major threat to the IV Corps' lines of communication.

To counter this threat the Finnish high command assembled the Group 'Talvela', which comprised the 16^th Jalkaväkirykmentti commanded by Everstiluutnantii Aaro Olavi Pajari, the 'Räsänen'
Irtautuminen (detachment) comprising the ErP 9, ErP 10, ErP 112 and PPP 7 independent battalions, and one battalion of the 6^th Tykistörykmentti (artillery regiment). The Finnish plan was to encircle the Soviet division by two pincer attacks over the frozen Hirvasjärvi and Tolvajärvi lakes. The northern attack over the Hirvasjärvi lake was to begin at 08.00 and the second when the first had started to yield results. This was later changed and both attacks were began at 08.00. The Finnish northern group of two battalions soon met Soviet resistance from the 718^th Regiment, which was preparing to make its own attack on the Finnish flank. By 12.00, the Finnish troops had withdrawn to their own lines. Although this attack did not fulfil its objectives, it did prevent the 718^th Regiment from attacking the Finnish flank, and also from sending reinforcements to the south. As it was preparing to attack along the road, the II/16^th Jalkaväkirykmentti was attacked by the 609^th Regiment but was still able to advance after it received artillery support. The Finnish attack continued toward a hotel located on a narrow isthmus between the two lakes, and Pajari decided to commit his reserve in a pincer attack on the Soviet troops around the hotel. In the end the hotel was captured and in it were found a dead Soviet regimental commander and all the regiment’s papers.

The Finns withdrew over the lakes for the night, and in the morning Talvela ordered a fresh attack, which drove the 139^th Division back and later, between 20 and 22 December, destroyed it in the area of the Ägläjärvi lake some 12.5 miles (20 km) from the Tolvajärvi lake. Contact was also made with the 75^th Division sent forward as a reinforcement. The Finnish losses were more 100 dead and about 250 wounded, while the Soviets are thought to have suffered more than 1,000 dead and more than 5,000 wounded out of some 20,000 men committed, as well as losing much equipment: the guns of two artillery batteries, anti-tank guns, some 20 tanks and 39 other armoured vehicles, and 60 machine guns.

The battle was an important offensive victory for the Finns and was very useful tonic for the morale of the whole Finnish army and nation.

In the south of the Ladoga Karelia front, the 168^th Division and 18^th Divisions fought their way forward to the north of the Lake Ladoga shore road before, as was now becoming all too disastrously evident to the Soviets, being halted and then trapped as the more mobile Finnish units, which counterattacked from the north to flank the Soviet columns. On 19 December, the Finns brought their assaults to a temporary halt out of sheer exhaustion.

It was not until the period between 6 and 16 January 1940 that the Finns went on the offensive again, cutting the Soviet divisions into mottis of different sizes. However, and contrary to Finnish expectations, the encircled Soviet divisions did not try to fight their way out to the east but instead started to throw up field fortifications in the expectation that they would be reinforced and supplied by air. As the Finns lacked useful quantities of medium and heavy artillery, in general they did not deliver direct attacks on all the mottis in which they had trapped the Soviets, but instead focused on destroying only the most threatening of them.

It is worth noting that the motti tactic was not part of any pre-planned Finnish doctrine, but rather a Finnish tactical adaptation to the behaviour of the Soviet troops, who tended to clump together in groups of varying sizes when they came under fire. Despite the bitter cold and ever-increasing hunger, the Soviets did not yield but instead resisted courageously, often entrenching their tanks to be used as pillboxes and building timber dug-outs. In these circumstance the Finns called in specialists in attacks on mottis, the most celebrated of these being Majuri Matti Aarnio, or 'Motti-Matti' as he became known, who was the commander of the IV Jalkaväkipataljoona (infantry battalion) but soon had eight battalions under his command for motti-destroying purposes.

In the northern part of the Ladoga Karelia front, the Soviet forces were outmanoeuvred at Ilomantsi and Lieksa, and in this part of the campaign the Finns made very effective use of guerrilla tactics, their white-clad troops exploiting their superiority in cross-country movement by ski and sledge to plan and implement a programme of surprise ambushes and raids. By the end of December, the Soviets decided to retreat in Ladoga Karelia so that they could transfer men and weapons to more critical fronts.

The most northerly of the fronts was that in Finnish Lapland. Here the forests become gradually thinner until in the north there are no trees at all. The area thus provides better opportunities for the deployment of armour, but in the winter of 1939/40 had only the sparsest of populations, and in winter suffers very heavy snowfalls. In this area the Finns expected nothing more than raiding parties and reconnaissance patrols, but instead the Soviets committed full divisions. On 11 December, the Finns rearranged the defence of Lapland and detached the Lapin Ryhmä (Lapland Group) from the Pohjois-Suomen (North Finland Group), placing it under the command of Kenraalimajuri Kurt Wallenius. In southern Lapland, near the rural village of Salla, the Soviet advance by the northern arm of the 9^th Army comprised the 122^nd Division, which was to have been followed by the 88^th Division, totalling 35,000 men; in the event the 88^th Division was not committed for lack of supplies. The 122^nd Division's task was to advance through Salla to Kemijärvi and Sodankylä, and thence Rovaniemi, which was to be reached in just two weeks. From there the division was to advance to Tornio, thereby cutting Finland in two.

It was in 1938 that the USSR had decided to conquer Finland. Relying in part on the information provided by Finnish communists, detailed intelligence on Finland’s infrastructure had been prepared by the summer of the following year and printed in a 200-page book that was distributed to the invasion forces. The9^th Army was tasked with invading Finland between Kuhmo and Salla and cutting the country in half by advancing to the shores of the Gulf of Bothnia. As part of the 9^th Army's offensive, the 122^nd Division, which had arrived from Poland on 8 November 1939, was to take Salla and Kemijärvi, and then to advance on Rovaniemi within two weeks, from where it would continue to Tornio near the Finnish/Swedish border. The Soviets expected only light resistance and the troops were ordered not to cross the Swedish frontier.

The Soviets began the construction of a railway line from Kandalaksha on the White Sea to the Finnish border using a labour force of 100,000 prisoners. In the late 1930s, moreover, the existing roads were improved and new roads built from the line of the Murmansk railway to the Finnish border: one of these was the road from Kandalaksha to Alakurtti.

The improvements in Soviet infrastructure and demographics in their border region, which made possible the supply of 40,000 troops had little effect on Finnish operational planning for operations in the northern part of Finland. The Finnish general staff did not believe the Soviets would launch a major offensive from the White Sea area into Finland. As a result, work on fortifying key road chokepoints in northern Finland started only in the autumn of 1939.

The forces in northern Finland were under the command of the staff of Kenraalimajuri Kurt Martti Wallenius’s Lapin Ryhmä (Lapland Group), which itself was commanded by the Pohjois-Suomen Ryhmä (North Finland Group). The Finns had the 17^th Erillinen Pataljoona detached battalion and the Erillinen Komppania Kojonen detached company near Salla with the task of conducting an active defence by crossing the border, stopping the advance of the Soviet regiment that was expected in the area and harassing the Soviet lines of communications, thereby tying down Soviet forces. The Finnish general staff considered the force insufficient for even this mission, but could not spare any more troops from the more important Karelian isthmus region. As Finland undertook a general mobilisation in October 1939, the troops had time to take stock of the situation and came to the conclusion that even limited offensive operations across the border were beyond their capabilities, so training was concentrated on only defensive and delaying operations.

After 5 December infantry, artillery, mortar and anti-tank units were despatched to the north for the reinforcement of the original defence force. The Finnish forces in the area totalled about 3,500 men.

A Finnish intelligence estimate on 15 October placed one Soviet division in the area of Murmansk and Kandalaksha, but the Finns expected a more substantial Soviet force concentration in the future: in fact, on 30 November the Soviets had four divisions in the area.

Some 80% of southern Lapland is covered by forests or swamps. The geography is dominated by forest-covered fells surrounding large swamps and lakes. In December 1939 the lakes and swamps were not yet sufficiently frozen to support the movement of motor vehicles but this became irrelevant as the winter progressed and the temperature dropped to -40° C (-40° F), which facilitated movement across ice but at the same time also made military operations more difficult in overall terms.

Off-road movement was thus impossible for large military formations and units. Only one road existed from the USSR to Salla. The road network was better developed to the west of Salla, and possessed numerous small roads to support lateral movements and the encirclement of defending forces.

In the Battle of Salla, which lasted from 30 November 1939 to 28 February 1940, the Soviets advanced easily to Salla, where the road forked, on 9 December and here divided their force as they continued to the west toward the Kemi river: the northern detachment moved via Savukoski to Pelkosenniemi, which it reached on 16 December, while the southern detachment pushed forward via Märkäjärvi toward Kemijärvi, which it approached but did not enter on 17 December. On this day the northern group (one infantry regiment, one infantry battalion, and one tank company) was outflanked by a Finnish battalion, the Osasto 'Suoranta' (detachment) and the 112^th Jalkaväkirykmentti retreated, abandoning much of its heavy equipment and vehicles. The Finns were now free to move reinforcements down to the defensive line in front of Kemijärvi, which the Soviets hammered unsuccessfully. The Finns of Majuri Vilho Roininen’s Osasto 'Roininen' counterattacked, and by 14 January the Soviets of the southern group had been pushed back to a new defensive line at Märkäjärvi, with the remnants of the northern group behind their right flank on the road between Savukoski and Salla. Here the the Soviets remained for the rest of the 'Talvisota' winter war.

From 10 February 1940 the Finnish troops were replaced by the 9,400 Swedish, Norwegian and Danish volunteers of the Stridsgruppen Svenska frivilligkåren (SFK, or Swedish Volunteer Corps) under command of the Swedish Generallöjtnant Ernst Linder. During the Battle of Salla, the Finns lost 650 men killed or missing, 450 wounded and 21 taken prisoner, and the Scandinavian volunteers 33 killed, 50 wounded and 130 frostbitten and seven taken prisoner. The Soviets lost as many as 4,000 men killed, wounded and taken prisoner.

In the extreme north of Wallenius’s command responsibility with the Lapin Ryhmä was Petsamo, Finland’s only ice-free port. The Finns lacked the manpower to defend this fully as the main front was clearly the Karelian isthmus, where Soviet success would threaten Viipuri and then Helsinki.

The resulting Battle of Petsamo was fought between 30 November 1939 and 12 March 1940 by wholly ill-matched forces comprising the 104^th Mountain Division and 52^nd Division of the Soviet 14^th Army and three Finnish companies commanded by Kapteeni Antti Pennanen. Despite the degree to which they were outnumbered and outgunned, the Finns managed largely to contain the Soviet troops as a result of the extreme terrain and weather. The Finnish troops consisted of the 10^th Er.K (separate company) in Parkkina and the 5^th Er.Ptri (separate battery) in Liinahamari. These units belonged to no specific division, and were therefore available for the creation of extemporised groupings. The troops were part of the Lapin Ryhmä headquartered in Rovaniemi. The troops were later reinforced by the 11^th Er.K and a 3^rd Er.K which was not part of the original mobilisation plan. The small 11^th Tiedusteluosasto (reconnaissance group) was also added to the Finnish strength on the north coast, which was the Osasto 'Pennanen'. On the other side of the frontier, the Soviets had Frolov’s 14^th Army in the Kola peninsula. This formation comprised the 104^th Mountain Division, 52^nd Division and 14^th Division, of which only the first two were involved in the Petsamo operations. The Soviets had an overwhelming superiority in troops in the area, but most of their strength was preparing to fight a possible British and French landing near Murmansk, and was therefore not involved in the fight against Finland.

Elements of the 104^th Mountain Division crossed the border on 30 November 1939 and occupied the Finnish part of the Rybachy peninsula. The 242^nd Regiment of the 104^th Mountain Division reached Parkkina on 1 December, and the Finnish troops withdrew to Luostari. The 52^nd Division was delivered to Petsamo by sea, and took over the attack from the 104^th Mountain Division, pushing back the Osasto 'Pennaanen' to Höyhenjärvi until the attack was halted on 18 December. During the following two months the Soviet forces made no farther advance, while the Finns made several reconnaissance and guerrilla raids behind the Soviet lines.

After a two-month pause, the Soviets resumed their advance and on 25 February drove the Finns back to Nautsi near the Inarijärvi lake, and then halted for the rest of the war. This small campaign had cost the Finns 89 killed, 135 wounded and 16 taken prisoner, and the Soviets 181 killed, 301 wounded and 72 taken prisoner.

Stalin was furious about the results of the first month of the Finnish campaign, in which the Soviet forces had been severely drubbed. By the third week of the war, Soviet propaganda was working hard to explain the failures by laying blame on the terrain and harsh climate of eastern Finland, and falsely claiming that the 'Mannerheim-linja' was stronger than the 'Ligne Maginot', and that the Americans had sent 1,000 of their best pilots to Finland. Shaposhnikov was now accorded full authority over operations in the Finnish theatre, and late in December ordered the suspension of frontal assaults. A change was also made in the theatre command, Voroshilov being replaced by Marshal Sovetskogo Soyuza Semyon K. Timoshenko on 7 January.

The primary focus of the offensive was switched to the Karelian isthmus as Timoshenko and Zhdanov reorganised and tightened control between different branches of service, and as they also changed tactical doctrines to meet the realities of the situation. The Soviet forces on the Karelian isthmus were now divided into two armies: Meretskov’s 7^th Army on the left and Grendal’s 13^th Army on the right.

The 7^th Army was now to up to three-quarter strength against the 10-mile (16-km) length of the 'Mannerheim-linja' between Taipale and the Munasuo swamp, and its tactics were to be simple: an armoured wedge for the initial breakthrough of the Finns' pinpointed front-line fortifications, followed by the main infantry and vehicle assault force. The 123^rd Assault Division, which was to spearhead the offensive, trained for its task on full-size mock-ups as the Soviets moved massive quantities of fresh armour and artillery into the theatre. The troop strength was boosted from 10 divisions to 25 or 26 divisions, six or seven tank brigades and several independent tank platoons, totalling 600,000 men.

Then, on 1 February, the Soviets began a massive offensive, dropping 300,000 shells onto the Finnish line in the first 24 hours of their initial bombardment. Though the Karelian isthmus front had been less active in January than in December, the Soviets had already begin to increased their artillery bombardments with the object of wearing down the defenders and damaging their fortifications. During daylight hours, the Finns took shelter inside their fortifications, and then emerged to repair the damage during the night. The situation led quickly to war exhaustion among the Finns, who lost more than 3,000 men. The Soviets also made occasional small assaults with one or two companies of infantry. Because of the ammunition shortage, the Finnish artillery was under instructions to fire only against directly threatening ground attacks. On 1 February, the Soviets further escalated their artillery and air bombardments. Although the Soviets had improved their tactics and morale of their ground forces had risen, the generals were still willing to accept massive losses in order to reach their objectives. Attacks were screened by smoke, heavy artillery and armour support, but the infantry charged in the open and in dense formations. Unlike their tactics in December, the Soviet armour was committed in smaller numbers, and the Finns quickly learned that the tanks were very difficult to destroy when they were protected by infantry.

After 10 days of round-the-clock artillery bombardment, the Soviets achieved a breakthrough on the Karelian isthmus in the 2^nd Battle of Summa. On 11 February, the Soviets had about 460,000 men in 19 or more divisions, more than 3,350 pieces of artillery, about 3,000 tanks in six tank brigades and a large number of infantry support units, and some 1,300 aircraft deployed on the Karelian isthmus, and were receiving fresh men in a constant stream after the breakthrough. Opposing them the Finns had eight divisions, totalling about 150,000 men. On the northern sector of the front, facing the area between Taipale and Vuosalmi as well as the north-eastern end of the 'Mannerheim-linja' as far to the south as the Muolaanjärvi lake, the 13^th Army had eight infantry divisions and one tank brigade as well as a number of other units, and was ordered to pin the Finnish formations opposite it; and on the western sector the front, between the Muolaanjärvi lake and the north coast of the Gulf of Finland, was the 7^th Army with 12 infantry divisions, five tank brigades and a number of other units. This was to attack first on its left wing with the object of drawing Finnish reserves as far to the south as possible, and then on its right wing with the object of securing a breakthrough between the Muolaanjärvi lake and Summa.

Thus the main weight of the Soviet offensive fell first on the Lähde sector some 6 miles (10 km) to the south-west of Summa: if they broke through there, the Soviets could them press on to the north-west and wheel to the north-east to fall on the right flank and rear of the Finnish forces holding the Summa position. Timoshenko knew that his forces had the strength to beat the Finns in a battle of attrition, and his plan was therefore to wear them down before committing his best formations in an intense final attack.

Within this plan, large probing actions were first launched against the Finnish lines, and for 10 days the Finns managed to hold firm. Then on 11 February the Soviets began their major assault, and on the following day managed to make a small breach in the Finnish line in the Lähde sector, which led to Finnish disaster. By that time, so many breaches had occurred in the 'Mannerheim-linja' that the reports concerning them were virtually disregarded. The Finns had ordered that on the morning of the next day a counterattack was to be launched by the entire 5^th Division, the only reserve in easy reach of the front line. However, only one of its three regiments was available as the other two had been used to reinforce regiments on other parts of the front. Thus only two Finnish battalions launched a counterattack against two well-supplied Soviet regiments well supported by armour and artillery. The Soviets drove back the counterattack, and in the process inflicted heavy losses on the Finns, and next attempted to exploit the salient they held. One tank regiment proceeded as far as the Lähde road junction but then, despite the fact complete victory lay in their grasp, the Soviets inexplicable brought their armoured spearhead to a halt. By this time many Finnish units had been reduced to half their original strength.

During the night of 14/15 February the Finns started to pull back from the Summa position. On the morning of 15 February the Soviets fell on a position at Summa with two divisions and more than 100 tanks only to find it deserted. During the afternoon of the same day Mannerheim ordered a general retreat by the II Armeijajunta from the Summa sector to the Välilinja (Intermediate Line.

On the northern sector of the Karelian front, meanwhile, the III Ameijakunta’s formations continued to resist Soviet assaults, repelling them in and to the west of Taipale.

Although the Finns had sought to re-open negotiations with the Soviets by every means available to them during the war, the Soviets had not responded. Early in January, the Finnish communist playwright Hella Wuoli contacted the Finnish government with an offer to contact Moscow through the USSR’s ambassador in Sweden, Alexandra Kollontai. Wuoli departed for Stockholm and met Kollontai secretly. Molotov soon decided to extend recognition to the Ryti/Tanner government as the legal government of Finland, and put an end to the puppet Teri government of Kuusinen which the Soviets had themselves established. By a time in the middle of February, it had become clear that the Finnish forces were on the verge of total morale and physical exhaustion, while the Soviet casualties had become extraordinarily heavy, the situation was a source of political embarrassment to the Soviet regime, and there was a risk of Franco-British intervention. Furthermore, with the spring thaw approaching, the Soviet forces risked becoming bogged down in the forests.

The Finnish foreign minister, Tanner, arrived in Stockholm on 12 February and negotiated the peace terms with the Soviets via Swedish intermediaries. Unaware that the negotiations were under way, German representatives suggested on 17 February that Finland negotiate with the USSR. Germany and Sweden each wished to see a speedy end to the 'Talvisota' winter war. The Germans feared losing the iron ore exported to them from the fields in northern Sweden, and threatened to attack at once if the Swedes granted the Allied forces right of passage. As the Finnish cabinet hesitated in the face of the harsh demands of the Soviet negotiators, King Gustav V of Sweden made a public statement on 19 February in which he confirmed having declined Finnish pleas for armed support. On 25 February, the Soviet peace terms were spelled out in detail, and on 29 February, the Finnish government accepted the Soviet terms in principle and declared that it was willing to enter into negotiations.

Meanwhile the 7^th Army had broken through the Intermediate Position and Rear Position of the 'Mannerheim-linja', and on 5 March had advanced 6.2 to 9.3 miles (10 to 15 km) past the latter to enter the suburbs of Viipuri, while other spearheads had taken Tali on 1 March and had reached the narrows separating the Vuoksijärvi lake and the Suvanto waterway to the west of Vuosalmi. On the same day, a force of the 28^th Division crossed the mouth of the frozen Bay of Viipuri to establish a beach-head at Vila to the south-west of Viipuri.

The Finns proposed an armistice on that same day, but the Soviets, wishing to maintain the pressure on the Finnish government, declined the offer the next day. The Finnish peace delegation went to Moscow via Stockholm and arrived on 7 March. The Soviets made further demands as their military position was strong and improving. On 9 March, the Finnish military situation on the Karelian isthmus was dire as their men suffered increasingly heavy casualties. Moreover, the Finnish supply of artillery ammunition was exhausted and weapons were wearing out. Noting that the Franco-British military expedition they had expected would not arrive in time, as Norway and Sweden had not given the Allies right of passage, the Finnish government had little choice but to accept the Soviet terms. The peace treaty was signed in Moscow on 12 March, and a cease-fire took effect the next day at 11.00 Helsinki time.

At this time the Soviet forces on the Karelian isthmus front were, from east to west, the 3^rd Division facing Taipale, the 15^th Division facing Vuosalmi, and the 23^rd, 19^th, 50^th, 34^th, 10^th and 28^th Divisions, and these faced the III Armeijakunta, I Armeijakunta and II Armeijakunta as well as the Rannikkoryhmä (Coast Group) created to check the 28^th Division's beach-head at Vilajoki.

The Soviets had enjoyed air supremacy throughout the war, but the Soviet air effort, in support of the land invasion with about 2,500 aircraft, was not as effective as the Soviets had expected. The material damage by the bomb raids was slight as Finland did not offer many valuable targets for strategic bombing, the country had only a few modern roads in its interior, and the railway system was therefore the bombers' primary target. Railway tracks were cut thousands of times, but were easy to repair and the Finns usually had trains running again in a matter of hours. The Soviet air forces learned from their early mistakes, however, and by a time late in February had started to use more effective tactics. The largest bombing raid was that against the capital of Finland, Helsinki, on the first day of the war, and the capital was bombed only a few times after that. All in all, Finland lost only 5% of total man-hour production time because of Soviet bombings. Nevertheless, Soviet air attacks affected thousands of civilians, killing 957 in what the Soviets reckoned as 2,075 bombing attacks on 516 places. Viipuri was almost wholly destroyed by nearly 12,000 bombs.

At the beginning of the war, Finland possessed only a very small air force, with only 114 serviceable warplanes. Missions were very limited, and fighters were used mainly to tackle Soviet bombers. Both obsolescent and few, Finnish aircraft were unable to offer any measure of direct support for the Finnish ground troops. In spite of losses, the number of aircraft in Finnish service had risen by more than 50% by the end of the war as a result of imports of British, French, Italian, Swedish and US aircraft. Finnish fighters shot down a confirmed 200 Soviet aircraft, losing 62 of their own. In addition, Finnish anti-aircraft guns brought down more than 300 Soviet aircraft. As well as their combat losses in about 44,000 sorties, the Soviet air force lost about 400 aircraft to inclement weather, lack of fuel and tools, and during movement to the front.

Naval activity during the 'Talvisota' winter war was very limited. The Baltic Sea began to freeze by the end of December, which made the movement of warships very difficult, and by mid-winter only ice-breakers and submarines could still move. The other reason for low naval activity was the nature of Soviet naval forces in the area. Vitse-Admiral Vladimir F. Tributs’s Baltic Fleet was essentially a coast-defence force without the training, logistical infrastructure and landing craft to undertake large-scale operations. The Baltic Fleet possessed two battleships, one heavy cruiser, almost 20 destroyers, 50 motor torpedo boats, 52 submarines, and a miscellany of other vessels, and used naval bases in Paldiski, Tallinn and Liepaja for their operations.

The Finnish navy was also a coast-defence force with two coastal defence ships, five submarines, four gunboats, seven motor torpedo boats, one minelayer and six minesweepers. The two coast-defence ships, Ilmarinen and Väinämöinen, were moved to the harbour in Turku, where they were used to bolster the air defences, and remained there for the rest of the war. In addition to its role in coastal defence, the Finnish navy protected the Åland islands group and Finnish merchant vessels in the Baltic Sea.

Soviet aircraft bombed Finnish vessels and harbours and dropped mines into Finnish seaways. Still, Finnish losses were relatively low, numbering 26 merchant vessels, only four of which were lost inside Finnish territorial waters. In addition to its navy, Finland had coastal artillery batteries to defend important harbours and naval bases along its coast. Most batteries were relics of the Russian period, with 6-in (152-mm) guns the most numerous weapons. Finland had attempted to modernise its old guns, however, and installed a number of new batteries, the largest of which featured 12-in (305-mm) weapons designed to block the Gulf of Finland to Soviet ships with the help of batteries on the Estonian side.

The first naval battle took place on 1 December, near the island of Russarö, some 3.1 miles (5 km) to the south of Hanko, after the Finns had spotted the Soviet cruiser Kirov and two destroyers. The Finns opened fire with 9.2-in (234-mm) coastal guns at a range of 26,250 yards (24000 m), and after five minutes of firing by four coastal guns, the cruiser had been damaged by near misses and pulled out of range. The destroyers remained undamaged, but Kirov suffered 17 dead and 30 wounded.

The coastal artillery had greater significance in the land war by helping to reinforce the defence in conjunction with army artillery. Two sets of fortress artillery made significant contributions to the early battles on the Karelian isthmus and in Ladoga Karelia fronts: these were located at Kaarna on the east of the isthmus and at Mantsi on the north-eastern shore of Lake Ladoga. Furthermore, the fortress of Koivisto provided similar support from the south-west coast of the isthmus. Coastal artilleries could fire 6-in (152-mm) shells to a range of 27,340 yards (25000 m).

World opinion largely supported the Finnish cause against Soviet aggression. Several foreign organisations sent material aid, and many countries granted credit and military matériel to Finland. Germany allowed arms to pass through Sweden to Finland, but after a Swedish newspaper made this fact public, Adolf Hitler initiated a policy of silence towards Finland, as part of improved German/Soviet relations following the signature of the Molotov-Ribbentrop Pact on 23 August 1939. Volunteers arrived in Finland from various countries. By far the largest foreign contingent came from neighbouring Sweden, which provided nearly 8,760 volunteers during the war. The Swedish Volunteer Corps (Svenska Frivilligkåren), with Swedes, Norwegians (727 men) and Danes (1,010 men), fought on the northern front at Salla during the last weeks of the war. A Swedish fighter unit operated in Finland with Gloster Gladiator biplanes, and Swedish anti-aircraft batteries with Bofors 40-mm guns were responsible for the air defence of northern Finland and the city of Turku. Volunteers also arrived from Estonia, Italy and Hungary. Some 350 US nationals of Finnish background volunteered, and 210 volunteers of other nationalities made it to Finland before the war ended. In total, Finland received 12,000 volunteers of whom 50 died during the war.

France was one of the earliest supporters of Finland during the 'Talvisota' winter war, the French seeing an opportunity to weaken the USSR, at that time Germany’s major ally, if the Finns were to attack the USSR. France also had other motives including a desire to have a major war fought in a remote part of Europe rather than on French soil. Among France’s plans were the rearmament of the units created from Poles who had escaped the defeat of their country in September 1939 for movement by sea to Petsamo, and a major bombing campaign, with Turkish co-operation, against the USSR’s oilfields in the Caucasus.

The British desired to prevent the flow of iron ore from Swedish mines to Germany as this constituted up to 40% of Germany’s requirements. The matter was first raised by Admiral the Hon. Sir Reginald Plunkett-Ernle-Erle-Drax on 18 September 1939, and on the next day Winston Churchill, then the First Lord of the Admiralty, brought the subject to the cabinet. On 11 December Churchill stated that the British should gain a foothold in Scandinavia with the objective of helping the Finns but without war on the USSR.

Because of Germany’s heavy reliance on Swedish high-grade iron ore, Hitler had made it clear to the Swedish government in December that the arrival of any Allied troops on Swedish soil would immediately provoke a German invasion. On 19 December the French prime minister, Edouard Daladier, introduced his plan to the general staff and the British war cabinet, suggesting a link between the war in Finland and the iron ore in Sweden. There was a danger of Finland’s collapse into the USSR. In turn, Nazi Germany could occupy both Norway and Sweden. These two dictatorships could divide Scandinavia between them, as they had already done with Poland. France’s main motivation was the export of the European battle front to Scandinavia in order to protect French soil, whereas the British were concerned with reducing the German war-making ability. The Franco-British Military Co-Ordination Committee met on the following day in London, and two days later the French plan was put forward. The Allied Supreme War Council elected to send notes to Norway and Sweden on 27 December in which they urged the Norwegians and Swedes to help Finland and offer the Allies their support. Norway and Sweden rejected the offer on 5 January 1940. The Allies then drafted a new plan to demand that Norway and Sweden give them right of passage by citing the League of Nations resolution as justification: the expeditionary troops were to disembark at the Norwegian west-coast port of Narvik and proceed by rail toward Finland, passing through the Swedish ore fields on the way. This demand was sent to Norway and Sweden on 6 January, but it too was rejected six days later.

Stalled but not yet dissuaded from the possibility of action, the Allies formulated a new plan on 29 January. First, the Finns would make a formal request for assistance. Then the Allies would ask Norway and Sweden for permission to move 'volunteers' across their territories. Finally, in order to protect the supply line from German actions, the Allies would send additional units ashore at Namsos, Bergen and Trondheim on Norway’s west coast. The operation would require 100,000 British and 35,000 French troops with naval and air support. The supply convoys would depart on 12 March for the landings to start on 20 March.

The Moscow peace treaty was signed on 12 March 1940 and went into effect on the following day. By this treaty, Finland ceded a portion of Karelia (the entire Karelian isthmus) as well as a large swath of land to the north of Lake Ladoga. The ceded area included Viipuri, which was Finland’s second largest city, much of Finland’s industrialised territory, and significant parts still held by Finland’s army: in all, 11% of Finland’s pre-war territory and 30% of its economic assets. Some 12% of Finland’s population, in the form of about 422,000 Karelians, were evacuated and lost their homes. Finland also had to cede a part of the region of Salla, the Kalastajansaarento peninsula in the Barents Sea, and four islands in the Gulf of Finland. The Hanko peninsula was leased to the USSR as a military base for 30 years. But the region of Petsamo, lost by the Finns during the war, was returned to Finland.

The 'Talvisota' winter war also cost Finland some 70,000 casualties in the form of 25,904 dead or missing, 43,557 wounded and 1,000 captured, as well as 957 civilians killed in air raids. The Finns also lost between 20 and 30 tanks, and 62 aircraft. The Soviets suffered about 323,000 casualties in the form of 126,875 men killed or missing, 188,671 wounded or injured, and 5,572 captured. The Soviets also lost 3,543 armoured fighting vehicles, and between 261 and 515 aircraft.