The 'Battle of Vevi', also known as the 'Battle of the Klidi Pass', was fought to the north of Amyntaion, close to the Greek north-western border, between German and Allied forces within the context of the German 'Marita' invasion (11/12 April 1941).

German forces had invaded Greece and southern Yugoslavia from Bulgaria, in 'Marita' and 'Unternehmen 25' respectively, during the first week of April 1941. After the collapse of resistance in Yugoslavia, the left flank of the 'Vermion Line' held by Greek and British and commonwealth forces became exposed. A revised plan intended that the British forces would hold the Germans forces in western Macedonia until Greek infantry units had withdrawn on foot from Mt Vermion to Mt Siniatsiko, and a new defensive line had been formed between Mt Olympus and the Aliakmon river.

On the morning of 10 April, General Georg Stumme’s XL Corps (mot.) of Generalfeldmarschall Wilhelm List’s 12^th Army advanced from Monastir to seize the Greek town of Florina, some 8.1 miles (13 km) to the south of the Yugoslav border, utilising the Monastir valley (or 'Monastir Gap'). The Leibstandarte SS Adolf Hitler, a brigade-sized Waffen-SS mechanised unit under the command of Obergruppenführer Josef 'Sepp' Dietrich and accompanied by Generalleutnant Alfred Ritter von Hubicki’s 9^th Panzerdivision, advanced farther to the south and occupied the town of Vevi on 11 April. Generalleutnant Bruno Bieler’s 73^rd Division followed the Leibstandarte SS Adolf Hitler and attacked to the west in order to widen the front of the German breakthrough. Confronting Ypostratigos Georgios Stanotas’s Greek Cavalry Division in an action at the Pisoderi pass, the 73^rd Division failed to make progress.

A mixed Australian, British, New Zealand and Greek formation, known as 'Mackay' Force was hastily assembled under the command of an Australian officer, Major General Iven G. Mackay, who deployed his headquarters in Perdika. Its task, in the words of the British commander in Greece, General Sir Henry Maitland Wilson, was to 'stop a blitzkrieg down the Florina Valley'.

The Klidi Pass, which links the towns of Vevi and Klidi to the south, is between 110 and 550 yards (100 and 500 m) wide and a winding defile with steep, rocky and treeless sides up to 3,280 ft (1000 m) in height.

During April 1941, conditions at the head of the pass were bitterly cold, with rain turning to snow. These conditions hindered the ability of the Allied infantry to sleep, especially the Australians and New Zealanders tired after a long and sudden journey from North Africa, and were neither experienced in nor equipped for warfare in wintry mountain conditions.

'Mackay' Force was deployed in two sub-sectors: the Greek forces around the town of Kelli, some 6.2 miles (10 km) to the east of the pass, and the British commonwealth forces in the pass itself. The latter comprised predominantly Brigadier G. A. Vasey’s Australian 19^th Brigade: the 2/4^th Battalion less one company and the 2/8^th Battalion, complemented by the British 9/King’s Royal Rifle Corps also known as the 1^st Rangers. The infantry were supported by parts of the New Zealand 27^th (Machine Gun) Battalion, the Australian 2/1^st Anti-Tank Regiment, the British 2^nd Regiment, Royal Horse Artillery and other smaller elements of Australian and British artillery units. Vasey’s headquarters were located a substantial distance away, approximately 6.2 miles (10 km) to the south of the town of Klidi.

Around the pass, Vasey’s three infantry battalions were spread across a front 9.9 miles (16 km) wide: the 2/8^th Battalion was on the ridge to the east of the pass, the 1^st Rangers on a north-facing spur on the western side, and the 2/4^th Battalion to the west of the Rangers on the Golema Glava height, which rises to 3,284 ft (1001 m). New Zealand machine gunners were distributed among the infantry, while the Australian and British artillery units were concentrated in the pass itself.

The Kelli sub-sector was covered by a Greek brigade-level force, primarily the Dodecanese Regiment (three battalions totalling 3,500 men), reinforced by the Greek X Border Sector (500 men), three Greek artillery batteries (one of mountain artillery, one of field artillery and one of anti-tank artillery) equipped with 75-mm (2.95-in) field guns, one engineer company and one machine gun company. The total strength of the Greek force, which was commanded by Syntagmatarchis Sergios Aristotelis, was about 5,000 men and 15 pieces of artillery. The 3/Dodecanese Regiment was deployed on the right flank of the British commonwealth units, on the Delinski Dol heights rising to as height of 3,900 ft (1200 m), followed by the 1/Dodecanese Regiment, the 2/Dodecanese Regiment and the X Border Sector to the far right. Two 75-mm (2.95-in) guns were sited in the anti-tank role between the 3 and 1/Dodecanese Regiment, controlling the road that passed through the village of Kelli.

Immediately to the west of 'Mackay' Force and covering its left flank, across the Radosi heights (Mala Reka ridge), were the 350 men of the Greek 1/88^th Regiment of the 21^st Brigade, part of the Cavalry Division.

The German force for the attack on the Klidi Pass was based on the 9^th Panzerdivision and the Leibstandarte SS Adolf Hitler. During its rapid advance through southern Yugoslavia, the 9^th Panzerdivision had formed an 'advance guard detachment' as the Vorausabteilung 'Appell' under Oberst Wilhelm von Appell, commander of the 9^th Schützenbrigade, which crossed into Greece together with the Leibstandarte SS Adolf Hitler. The action was also supported by artillery of the XL Corps (mot.).

On the right flank, the Vorausabteilung 'Appell' comprised the staff of the 9^th Schützenbrigade (mot.), one battalion of the 9^th Aufklärungsregiment, the 1/11^th Schützenregiment, the 2/102^nd Artillerieregiment less one battery, one battery of the 86^th Flakabteilung, one company of the 50^th Panzerjägerabteilung and one company of the 86^th Pionerabteilung. Also available to the German commander were some of the XL Corps (mot.) assets in the form of the 2/37^th schwere Artillerieabteilung with 12 150-mm (5.91-in) guns and one battery of the 29^th Beobachtungsabteilung for counter-battery fire.

The Leibstandarte SS Adolf Hitler deployed its elements with the reinforced 1/Leibstandarte SS Adolf Hitler and the Kampfgruppe 'Witt' on the right to attack the Vevi Pass frontally, and on the left the reinforced 3/Leibstandarte SS Adolf Hitler to attack the recognised key point of the forthcoming battle in order to achieve a breakthrough from Kelli toward Amyntaio. The 2/Leibstandarte SS Adolf Hitler, less two companies, was to remain in Florina as a reserve and to secure the area from the south and west. The reconnaissance group (under SS-Hauptsturmführer Kurt Meyer, commander of the SS Aufklärungsabteilung 'Leibstandarte') was initially ordered to link with the 2^nd Panzerdivision near Edessa, although this plan was later changed so that the reconnaissance group pursued the Allied forces toward Sotir after the pass had been opened. To support the Kampfgruppe 'Witt', the 5/Leibstandarte SS Adolf Hitler, a so-called heavy battalion, detached 15 tracked self-propelled pieces of artillery, comprising its battery of six Sturmgeschütz III assault guns with 75-mm (2.95-in) guns and its anti-tank company of nine Panzerjäger I machines armed with 47-mm guns. The Leibstandarte SS Adolf Hitler's pioneer battalion was to remain behind the Kampfgruppe 'Witt' awaiting orders to undertake tasks such as mine clearance and road repair. One light howitzer battery was to provide direct support to the 3/Leibstandarte SS Adolf Hitler, and a heavy howitzer battery to the Kampfgruppe 'Witt'. The Leibstandarte SS Adolf Hitler's artillery regiment, less one 88-mm (3.465-in) Flak battery, was to co-ordinate its actions with the Kampfgruppe 'Witt'.

SS-Sturmbannführer Fritz Witt commanded the Kampfgruppe 'Witt', which comprised the reinforced 1/Leibstandarte SS Adolf Hitler, five companies of the 2/Leibstandarte Adolf Hitler, one machine gun company of the 2/Leibstandarte SS Adolf Hitler two 'light infantry weapon' platoons,
one 'heavy infantry weapon' platoon, three anti-tank platoons, two engineer platoons, one light field howitzer troop, one 88-mm (4.365-in) Flak platoon and a number of StuG III and Panzerjäger I tracked vehicles. Neither the Germans nor Allies believed that armoured vehicles would be able to climb the extremely rocky slopes surrounding the pass.

The boundary between the Leibstandarte SS Adolf Hitler and the Vorausabteilung 'Appell' was about 1.25 miles (2 km) to the west of the road linking Niki and Klidi via Vevi, and parallel with it. The missions assigned to these German units were: the Leibstandarte SS Adolf Hitler was to open the pass while the Vorausabteilung 'Appell' was to move, after the Leibstandarte SS Adolf Hitler's attack, from the area of Flambouron toward Aetos and Xino Nero, and thus into the rear of the forces defending the pass.

At 00.00 on the night of 10/11 April, on the Dodecanese Regiment’s front, the Germans attempted reconnaissance patrols and probing attacks against Glava hill but were repelled after a two-hour battle. The Germans repeated these actions at 14.00 against Delinski Dol but were also driven back.

The Waffen-SS unit did not probe the British commonwealth forces' front until the afternoon of 11 April. This included an encounter with Australian artillery positions on the main road. Captain Gordon Laybourne Smith of the 2/3^rd Field Regiment later commented that the German commander had sent 'in all his insolence…trucks down the main road…to within 3,000 yards [2745 m] of our infantry, and proceeded to debus. At first I could not believe it was an enemy, all had been so still and quiet. Then came some sense. My orders flew over the wire and the first rounds screamed through the air…A few furious moments and back went the Hun, but five trucks stayed in the road as silent witness that my troop could shoot.' More prolonged skirmishes were directed at the positions of the 2/8^th Battalion, and these became more aggressive as night approached.

By the morning of 12 April, the sides of the area’s hills had a covering of fresh snow more than 12 in (30.5 cm) thick. By dawn, many of the Australians and New Zealanders stationed in the hills were suffering from frostbite and were unable to work their weapons effectively. Orders had now been issued, however, for an orderly withdrawal to the 'Aliakmon Line', to begin that evening.

At 08.30 or 09.00 on 12 April, the Germans launched their main assault. Without artillery preparation, the 1^st Kompanie of the Leibstandarte SS Adolf Hitler, serving as the vanguard of the Kampfgruppe 'Witt' on its left flank, attacked the key Hill 997, which was held by one company of the 2/8^th Battalion under the command of Captain Bill Robertson. After hard close-quarter fighting, by 11.00 the Germans had taken the hill, in the process overrunning an Australian platoon of which only six men survived. At 12.30 the 7^th Kompanie of the Kampfgruppe 'Witt' extended the attack toward Hill 917, which it had taken by 14.00 in the face of strong resistance. The hill had been defended by an Australian company under Captain Coombes at the far left of the 2/8^th Battalion’s sector, near its junction with the 1^st Rangers.

According to the Australian official history, at 11.00 the 1^st Rangers, possibly in the belief that that the 2/8^th Battalion was retreating, began to withdraw. This opened the pass to the Germans, created a gap between the 2/4^th Battalion and 2/8^th Battalion, severed communications between Vasey and the 2/8^th Battalion and left Australian anti-tank guns without infantry protection. To the west of the battlefield, the Greek 21^st Brigade reported at 12.00 that it had lost contact with the 2/4^th Battalion. At 13.00, the Dodecanese Regiment reported that the 2/8^th Battalion was retreating, although the regiment itself had yet to receive any such order. The two companies of the 2/8^th Battalion on the western flank (Coombes’s and Robertson’s companies), were forced to retreat up the slopes.

However, in the words of the Australian official historian, 'At 2:00 pm…Lt.-Col. [John] Mitchell of the 2/8^th… ordered a counter-attack which regained some vital ground on top of the ridge…After six hours of intermittent fighting in the pass and on the slopes to the east, the 2/8^th still held the Hills though their left had been mauled; the Rangers, however, were rallying astride the road about two miles [3.2 km] to the rear, but five of the six supporting guns of the 2/1^st Anti-Tank Regiment had been left without protection and abandoned. Thus the ridge held by the 2/8^th formed a deep salient.'

According to one account, Vasey was informed of the Rangers' withdrawal by officers of other units, but refused to believe it. The line of the Dodecanese Regiment began receiving artillery fire at 14.30, concentrated mostly on Delinski Dol. In the west, the Greek 21^st Brigade reported from 14.30 that groups of Australians were retreating to the south in the direction of Xino Nero.

From 14.35 a number of Sturmgeschütz and Panzerjäger vehicles had arrived to support the 1^st Kompanie and 7^th Kompanie of the Kampfgruppe 'Witt'.

After the earlier German successes, the 2^nd Kompanie of the Leibstandarte SS Adolf Hitler and a heavy machine gun platoon attacked to the west of the road, with the 3^rd Kompanie astride and to the east of the road. The 7^th Kompanie attacked from Hill 917 to the west of Klidi village and the 1^st Kompanie from Hill 997 to the east of Klidi village. By 15.30, the 2^nd Kompanie and 3^rd Kompanie had captured Hill 1009 in the 1^st Rangers' sector, in the process reducing the British machine gun positions with heavy weapons. At 16.00 the forces opposing the Kampfgruppe 'Witt' began to retreat, carrying out road demolitions as they pulled back. The Kampfgruppe 'Witt' attacked, and pioneers coming behind the 3^rd Kompanie started to open a corridor in the Allied minefield, and this eventually made it possible for two assault guns to pass through. Simultaneously, the 3/Leibstandarte SS Adolf Hitler and the Vorausabteilung 'Appell' began their attacks.

As the German artillery fire on the Greek lines intensified, at 15.40 Mackay ordered the Dodecanese Regiment to retreat immediately and to have evacuated its positions by 18.00, one hour earlier than originally scheduled. At 16.30, the Dodecanese Regiment began its withdrawal after destroying its artillery as this could not be evacuated. When the Dodecanese Regiment began its retreat, it reported that no British commonwealth forces were to be seen in the Kirli Derven sector, and according to German sources the 3/Leibstandarte SS Adolf Hitler began its attack toward Kelli at 16.20.

At 16.00, in the west, the German attack was extended against the Greek 1/88^th Regiment, which began taking artillery and mortar fire. Between 16.30 and 18.00, a force reported by the Greeks as elements of the German vanguard, primarily one battalion of the 9^th Aufklärungsregiment and the 1/11^th Schützenregiment, concentrated against the battalion’s sector on Radosi hill, and approached to assault distance under Greek harassing fire.

The 2/8^th Battalion had been exposed on both its flanks by the Greek and British withdrawals, and soon came under German machine gun fire from the east. According to an official Australian account, Vasey 'realised his men were not going to be able to stage an orderly withdrawal. At 17:00, he telephoned the commanding officer of the 2/4^th Battalion…with the code phrase ['the roof is leaking'] indicating that a pull-out was now vital.' At 17.30, the Australian official history reported, 500 German infantrymen supported by self-propelled guns attacked along the width of the 2/8^th Battalion’s sector. Meyer, a German participant in the battle, wrote later of his surprise at how easily the heavy assault guns had climbed the slopes: 'We watched the guns advance in amazement. They climbed higher and higher, and then joined the fight. Nobody [had] thought it possible to use them, but now they were up there, giving valuable support to the infantry. Completely shaken by the impression German shelling had made on them, British [sic] prisoners came down the mountain. They were tall, strong fellows and formidable opponents.' The assault guns effectively sealed the German victory at Vevi. The 2/8^th Battalion was forced into a chaotic retreat in which its component units became separated and officers ordered the abandonment of even light weapons, to speed the withdrawal. Australian infantry losses would have been much worse had it not been for the 2/1^st Anti-Tank Regiment and the British Royal Horse Artillery, which stood their ground in the centre, until the Germans were only 440 yards (400 m) distant.

According to German sources, at 18.00 the 7^th Kompanie and 1^st Kompanie of the Leibstandarte SS Adolf Hitler captured the village of Klidi and took 82 prisoners. A short time later, the 3^rd Kompanie captured the exit of the rail tunnel, in the process taking another 250 New Zealand, British and Australian prisoners. Greek and German sources agree that the 3/Leibstandarte SS Adolf Hitler reached Kelli at 18.15 and then occupied vacated Greek positions, and reached Petra by 20.15. However, German sources report that some Greek units were still fighting to the far east of the sector at 20.00, when 40 Greeks and 60 Australians were taken prisoner.

The early collapse of the British commonwealth forces' lines in the Klidi Pass made it possible for the German forces to advance south of the pass before the Dodecanese Regiment had completed its withdrawal to the west. The Greek regiment’s right-hand column, comprising the first and third battalions as well as the regimental headquarters, was attacked by 'about 20 German tanks' (in reality six assault guns and nine tank destroyers) at 18.00 to the west of Amyntaion, with fire from a range of between 880 and 1,100 yards (800 and 1000 m. The column was saved by the timely intervention of some 25 to 30 British tanks that prevented the capture of the Greek force.

To the west, the positions of the Greek 88^th Regiment came under attack at 18.30. After a brief and uneven close-quarter fight, the Germans overran the 88^th Regiment, whose remnants reeled back toward Aetos. According to Greek sources, an attempted counterattack was aborted when the 88^th Regiment’s commander was killed, but German sources mention that a Greek attack against the German right flank was repulsed at 19.00.

Meanwhile, to the east, at 19.00 the 12^th Kompanie and 13^th Kompanie of the 3/Leibstandarte SS Adolf Hitler advanced to the east over 'Hill 1202' (presumably Delinski Dol, which is noted on Greek maps as Hill 1200), while the 14^th Kompanie moved to the west of Lake Petron to the village of Petres. The 2^nd Kompanie, followed closely by the 3^rd Kompanie, attacked astride the road, while the 1^st Kompanie and 7^th Kompanie came down from the hills flanking the pass toward Sotir. At 21.00 operations came to an end along a line extending from the east of Xino Nero almost to Sotir.

At 20.00, the remnants of the Greek 88^th Regiment had started to reach Aetos after suffering the loss of 11 men killed, 18 wounded (including its commander) and 96 taken prisoner (some of them wounded). The 88^th Regiment began to reorganise, although its numbers were now sufficient to form only one company. The German casualties were reported by the Greeks as 'heavy'.

German sources also report that elements of the Vorausabteilung 'Appell' captured Hill 966 (Seveskeravi hill) at 22.30 after hard fighting against Australians. However, this hill was in the Greek sector and is not mentioned in the Australian or Greek official histories.

The 2/8^th Battalion had been in effect destroyed as a fighting unit for the rest of the Greek campaign. According to some accounts, at its fallback position of Rodona, the battalion could muster only 250 men, of whom only 50 had weapons. Although the 2/4^th Battalion had been spared the brunt of the German assault at Vevi, some 70 of it men were taken prisoner at a German roadblock during the battalion’s retreat to Sotir. The Germans claimed 480 'English' had been taken prisoner at Vevi for the loss of 37 men dead, 95 wounded and two taken prisoner.

Although it had been defeated and suffered heavy losses in its actions at Vevi, the 'Mackay' Force had succeeded in gaining two days for the retreat and regrouping of Allied forces to the south. Despite this, by the time the Allied resistance at Klidi collapsed, the Greek 20^th and 12^th Divisions had yet to complete their withdrawal, and subsequently found themselves defending their positions on the Mt Siniatsiko line (the passes of Kleisoura, Vlasti and Siatista) under very unfavourable conditions. The Dodecanese Regiment, the most combat-worthy of the 20^th Division’s units, was scattered during its withdrawal to the west as a result of misunderstandings with the British, who undertook the regiment’s transport on lorries as the regimental commander chose not to appear at the selected rendezvous with the regiments 1^st and 3^rd Battalions, and remained instead as the reserve of the 20^th Division for the remainder of the war. Most of the 20^th Division was still straggling westward toward Mt Siniatsiko when the Leibstandarte SS Adolf Hitler made contact with the main defensive line at Kleisoura in the evening on 13 April.

The 12^th Division, retreating through snow storms over Mt Vermion, was still to the east of the road linking Florina and Servia when the 'Mackay' Force retreated from Klidi. Although Brigadier C. W. M. Norrie’s British 1^st Armoured Brigade fought delaying battles at Sotir and Proastio during 13 April, covering the 12^th Division’s withdrawal, the latter was eventually split by the German advance, losing three of its battalions which were cut off the main body and retreated to the south in the direction of Servia. When the 9^th Panzerdivision reached the Siatista defensive location at 13.30 on 14 April, only one battalion of the 82^nd Regiment was in position. When expecting the German assault on the Siatista pass on 15 April, the 12^th Division could muster only 1,000 men as an effective strength, and was both demoralised and exhausted.