This was a German, Italian and Croat three-stage offensive against the partisan forces of Josip Broz Tito, and known to the Yugoslav forces as the 'Fourth Enemy Offensive', in Axis-occupied Yugoslavia (20 January/April 1943).
The Axis partners in fact launched a series of five offensives as a result of Adolf Hitler’s Führerweisung Nr 47 of 28 December 1942, which established a south-eastern theatre in the Balkans under the Oberbefehlshaber 'Südost', Generaloberst Alexander Löhr, who was answerable directly to Hitler. In this directive Löhr was ordered to undertake the 'final pacification of the hinterland and destruction of the rebels and bandits of all kinds, in conjunction with the Italian 2nd Army', and decided that the first step in this programme required the elimination of the partisan forces in Croatia and Bosnia.
'Weiss' (ii) was initiated to secure this objective, and for the task Löhr gathered a force of six German, three Italian and two Croat divisions as well as a number of anti-communist Četnik and Ustase units. Under the command of Generalleutnant Rudolf Lüters, the Befehlshaber der Deutschen Truppen in Kroatien, an extemporised corps command controlled SS-Gruppenführer und Generalleutnant der Waffen-SS Artur Phleps’s 7th SS Gebirgsdivision 'Prinz Eugen' at Karlovac, Generalleutnant Fritz Neidholdt’s 369th Division (kroatisch) at Banija, one regiment of Generalleutnant Josef Brauner von Haydringen’s 187th Reserve-Division, Generalleutnant Karl Eglseer’s 714th Division, Generalleutnant Benignus Dippold’s 717th Division at Sanski Most, and the Croat Home Army's 2nd and 3rd Home Defence Mountain Brigades. Generale di Corpo d’Armata Mario Robotti’s Italian 2a Armata provided Generale di Divisione Pietro Scipione’s 57a Divisione 'Lombardia', Generale di Divisione Furio Monticelli’s 12a Divisione 'Sassari' and Generale di Brigata Giovanni de Bonis’s 13a Divisione 'Re', and the Axis force was completed by some 20,000 Četniks. The Axis forces could thus deploy some 150,000 troops against the considerably smaller partisan strength.
The operation was schemed in three stages as 'Weiss I' (20 January/15 February) involving attacks on the partisan-held areas in western Bosnia and parts of central Croatia, 'Weiss II' (25 February/mid-March) involving operations in western and south-western Bosnia, forcing the partisans to retreat as far to the south-east as the Neretva river, and 'Weiss III' (launched in March by Italian forces) centred around the areas of northern Herzegovina, though the targeted partisans managed to breakout from an encirclement into northern Montenegro, and the third phase was not successfully completed.
In 'Weiss' (ii), the Germans aimed to destroy the central command structure of the partisan movement, known as the Central Committee of the Communist Party of Yugoslavia, as well the main strength of partisan units grouped around this headquarters, and for the task the Axis allies mustered 10 divisions, with about 90,000 men, and 12 squadrons if aircraft. Četnik auxiliaries and units, totalling between 12,000 and 15,000 men also took part, and these worked closely with the Italians.
The operation coincided with the so-called 'March on Bosnia', a plan based on the use of Četnik forces from Lika, northern Bosnia, northern Dalmatia, Herzegovina and Montenegro to undertake the destruction of the partisan forces holding territory in those areas. The 'March on Bosnia' also called for the 'ethnic cleansing' of the Moslem population in Bosnia and Herzegovina and in Sandzak. According to the Germans, the Četnik forces comprised 150,000 men in February 1943, an increase of 50,000 men since August 1942.
The partisans totalled something less than one-third of the Axis figure. On 2 January Draza Mihailović reported on the plan to his Četnik forces, calling for the destruction of the partisans' so-called Bihać Republic in order to 'liberate this Serb territory from communist terror;, and 19 days later he wrote: 'Indeed, the question of Bosnia is most important. In western Bosnia and Lika we are currently making the final preparations for the definitive destruction of the communists, who are preventing us from destroying [Anton] Pavelić's Croatia.'
The operation’s orders mandated extreme severity toward captured partisans and the civilian population. The former were to be shot after capture, and civilian populations deemed hostile were to be deported to transit camps. Villages in the combat area were to be razed to the ground. The commanders on the ground were prohibited from punishing their subordinates for excessive harshness.
In the 'Weiss I' four German divisions (SS-Gruppenführer und Generalleutnant der Waffen-SS Artur Phleps’s 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen', Generalleutnant Fritz Neidholt’s 369th Division, Generalleutnant Josef Reichert’s 714th Division and Generalleutnant Benignus Dippold’s 717th Division) were to attack from the arc extending from Karlovac across Glina, Kostajnica, Bosanski Novi and Sanski Most towards the line linking Bihać and Petrovac. Three Italian divisions (Generale di Brigata Francesco Zani’s 57a Divisione 'Lombardia', Generale di Brigata Pietro Scipione’s 13a Divisione 'Re' and Generale di Brigata Ettore Giannuzzi’s 12a Divisione 'Sassari') were to advance on the Germans' right wing, through Lika and northern Dalmatia. According to the plan, the 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen' and 717th Division, deployed deployed on the extreme ends of the arc, were to race into the partisan rear areas with motorised Kampfgruppen and meet at Vrtoče on the second day of the operation. The reinforced 369th Division and 714th Division were to link with them and close the net round the bulk of the partisan forces in the area of the Grmeč mountain. In the final stage, three divisions were to destroy the encircled partisans, and to deport the civilian population and thus prevent any possibility of the revival of partisan activity in the area.
German divisions were reinforced with the German 202nd Panzerabteilung and the Croat 2nd Home Guard Mountain Brigade and 3rd Home Guard Mountain Brigade. Italian divisions used the Lika, Dalmatia and Herzegovina detachments of Četnik auxiliaries, the Ustase 31st, 32nd and 34th Battalions and the 2nd Jäger Home Guard Battalion.
On 8 January the partisans' 2nd and 5th Krajina Brigades moved to Kozara and launched a series of attacks on the Croat garrisons and positions in Lijevče polje. These attacks coincided with the attacks of Major General Koča Popović's 1st Proletarian Division in central Bosnia, so Lüters decided to exclude the 714th Division from the operation Weiss and therefore have it available for the defence of the Banja Luka area. As the 718th Division was already engaged in anti-partisan operations in the central and eastern parts of Bosnia, Lüters reinforced the 369th Division with one regimental combat group of Generalleutnant Josef Brauner von Haydringen’s 187th Ersatz-Division.
The convergent Axis offensive began on 20 January, but none of the divisions succeeded in keeping to the planned schedule. The Axis forces attacked the territory controlled by Colonel Ivan Gosnjak’s I Croat Corps and Colonel Kosta Nađ's I Bosnian Corps in the areas of Banija, Kordun, Lika and western Bosnia. On the Karlovac/Bihać axis, four partisan brigades defended against the attack of the 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen': thesed partisan units were the 4th and 15th Brigades of the 8th 'Kordun' Division and the 6th and 14th Littoral-Gorski Kotar Brigades. The 7th Banija Division was successful in containing the advance of the 369th Division from Glina and Kostajnica toward Cazin and Bosanska Krupa. The 6th 'Lika' Division held the Plitvička Jezera/Gračac line against Italian attacks.
The 717th Division encountered difficulties while trying to reach Bosanski Petrovac from Sanski Most. The division began its attack on 20 January with the 749th Regiment and elements of the 202nd Panzerabteilung. Despite the fact that the German ground thrust had air support, it was halted by the 1st Krajina Brigade and one battalion of the 7th Krajina Brigade some 6 miles (10 km) to the south of Sanski Most. The 717th Division's 737th Regiment was in reserve, waiting to exploit a breakthrough, but the 749th Regiment failed to make one. During the following days, each side stepped up its effort, increasing its strength at the key point, but the partisans steadfastly blocked the German attacks while launching their own fierce counterattacks by night. The 717th Division attempted a diversionary attack from Sanski Most to the west with the 2nd Home Guard Mountain Brigade. On 25 January this battle group of two Croat home guard battalions and one German company were attacked by the 1st Battalion of the 6th Krajina Brigade and the 3rd Battalion of the 1st Krajina Brigade, but the German and Croat effort was routed with heavy losses, and the partisans seized much in the way pf weapons, their haul including 40 light and 10 heavy machine guns, four mountain guns and one anti-tank gun. The commander of the 717th Division, Dippold reported to Lüters that on 26 January the 2nd Home Guard Mountain Brigade had been completely shattered, and that the remnants of the 2nd and 4th Battalions had been absorbed into the 749th Grenadierregiment. The more ambitious attack directed to the west was launched on 27 January with the reinforced 737th Regiment, and this reached Benakovac before being halted by the 6th Krajina Brigade. In the meantime, the 2nd and 5th Krajina Brigades arrived from Kozara as reinforcements, and the 737th Regiment suddenly found itself in a difficult situation. Seeing no alternative, the regiment established an all-around defence, and remained isolated and under attack until 3 February.
Simultaneously, the 717th Division resumed the attack on the main partisan force toward Ključ and Bosanski Petrovac. The attack was scheduled to begin in the early hours of 28 January, but battalions of the 1st Krajina Brigade surprised the Germans during the night with a spoiling attack on their start positions and scattered the German units. On the next day the Germans launched a tank-spearheaded attack with the intention of collecting weapons and stragglers, but partisan anti-tank fire destroyed the first tank, killing Oberstleutnant von Geyso, the commander of the 202nd Panzerabteilung.
The partisan defence line, which had withstood most of the German attacks up to this time, was finally compromised by the advance of the 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen' which, with the support of two Italian divisions on the right flank, steadily pushed back the four partisan brigades, capturing Slunj and Rakovica on 24 and 27 January respectively. As a result, Bihać came under threat and had to be evacuated, and Germans entered it on 29 January without a fight. This also compromised the position of the 7th 'Banija' Division in the Banija region. This partisan formation was instructed to withdraw and occupy a new line in front of the 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen', covering the Bihać/Petrovac axis. Thousands of refugees left Banija together with the partisan formations and units, in the process suffering air attack, hunger, frost and disease.
The 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen' continued to push in the direction of Petrovac against partisan defences comprising primarily the 7th 'Banija' Division. It took another 10 days for the Germans to cover those 30 miles (50 km) to Petrovac, which the 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen' reached on 7 February before managing to link with the 717th Division on 9 February and thus finally achieve the task originally scheduled for the second day of 'Weiss' (ii). The 369th Division and the 3rd Home Guard Mountain Brigade, opposed only by partisan rearguards, reached Bosanska Krupa on 30 January and relieved the encircled 737th Regiment at Benakovac on 3 February. One day later the 369th Regiment joined the 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen' near Bihać. With this, the Grmeč area was encircled by three German divisions. On 6 February, after they had received reinforcements, the 369th Division, 187th Ersatz-Division and 717th Division started their attack on Grmeč. The 2nd and 5th Krajina Brigades were caught in the encirclement, along with some 15,000 inhabitants. On 10 February the brigades made the decision to break through the German encirclement, and succeeded in opening the road linking Krupa and Sanski Most road toward Potkalinje. The local civilian population followed the partisan brigades, but up to 2,000 of them succumbed to the freezing weather. Some 400 of the remaining civilians were killed by the Germans.
According to a German report of operations of 18 February for 'Weiss I', the 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen' suffered losses of 149 dead, 222 wounded and 68 missing, and the 717th Division's casualties were 118 dead, 290 wounded and 20 missing. The same report puts the Partisan losses at 6,561 dead, but adds that only 286 rifles were captured. This drastic imbalance between the figures suggests that those killed were mainly civilians.
During the first half of 1942 the partisans were driven from the eastern parts of Yugoslavia, and the Axis powers in general succeeded in securing the pacification of these areas. The partisans established a stronghold in the western parts of the country, but a return to the eastern areas remained one of their primary objectives. The localisation of partisan activity made it possible for the Germans to leave control of pacified areas to second-line forces, and to concentrate their better formations and units in areas facing a greater partisan threat. The 714th Division, 717th Division and 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen', which had been operated in the western part of Bosnia in January 1943, were then deployed in Serbia. Josip Broz Tito, the partisan leader, started to plan an offensive toward the east early in the autumn of 1942, but the original concept had been to start this large-scale movement in the spring, but evidence of an imminent Axis offensive in January 1943 made Tito order the start of the operation without delay.
The operation was to be carried out in three stages: the first was an advance to the area of the Neretva river, the second from the Neretva river to the Drina river, and the third from the Drina river to the Lim river and farther to the south-east. The main object of this partisan undertaking was the revival of the partisan presence and activity in these areas. On 8 February in Tomislavgrad, Tito presented the plan for the first stage in a conference with the staffs of the 1st Proletarian Division, 2nd Proletarian and 3rd Assault Division, and then issued the necessary orders and directives.
The execution of the offensive was facilitated by the fact that the so-called Main Operational Group of three divisions deployed by Tito were located outside the area affected by 'Weiss I'. The most distant unit, Popović's 1st Proletarian Division, was ordered to start preparations for the required approach march late in January. The Main Operational Group was divided into three columns: The right-hand column was based on the 2nd Proletarian Division and was to advance over Imotski, Posusje and Dreznica with the aim of cutting communications in the Neretva river valley, and of protecting the right flank of the partisan main force against the Axis garrison at Mostar; the central column was based on the 3rd Assault Division and was allocated the most difficult task in the form of taking Gornji Vakuf, Prozor, Ostrozac on the Neretva river and Konjic, and of opening the way across the Neretva river at Konjic; and the left-hand column was based on the 1st Proletarian Division and was to advance over Gornji Vakuf, Solakova Kula, Bradina and the Ivan sedlo pass, protecting the right flank of the partisan main force against the Axis garrison at Mostar, destroying all traffic installations between Konjic and Sarajevo, and providing protection for the partisans' northern flank against possible Axis intervention from Sarajevo by securing the Ivan sedlo main mountain pass.
The 7th 'Banija' Division was to be the Main Operational Group’s rearguard and to protect the recently formed 'Central Hospital' in which some 4,000 sick and wounded were being treated. Created to provide for the wounded, who were routinely targeted for execution by the Axis forces, the 'Central Hospital' by its very existence exercised a profound impact on the course and outcome of future operations.
The right-hand column began its advance with easy victories over the Croat garrisons of Posusje and Imotski on 9 and 10 February. On 15 February the column reached the Neretva river and attacked the small Italian garrison in Drezinca. The 1/260a Reggimento of Generale di Divisione Paride Negri’s 154a Divisione da occupazione 'Murge' intervened from Mostar, but was almost completely destroyed on 16 February with the loss of 120 men killed and 286 taken prisoner (including the commander, Tenente Colonnello Francesco Metella) and all of its equipment. The partisans sent a messenger to Mostar with a proposal fo a prisoner exchange, but nothing happened.
With this success, the 2nd Proletarian Division gained control of the Neretva river valley in the area to the north of Mostar, and severed all contact between the town and the Italian garrisons farther to the north. The Italian command had by now come to the appreciation that the Mostar garrison was seriously endangered, and therefore decided on the immediate mobilisation of all available Četnik units. The Italians had agreed initially not to use the Montenegin Četniks in supposedly independent Croatia, but now had to reverse this decision in the face of the looming threat to their interests in Herzegovina. On the other side of the line, the 2nd Proletarian Division felt confident in its new position. As it had fulfilled its main task, the division sent its 4th Proletarian Brigade to the north in order to assist the central column.
In the opening phase of the partisan offensive, the central column captured Gornji Vakuf on 30 January, and by 8 February was readying itself for an attack on the Italian garrison of Prozor, namely the 3/259o Reggimento, reinforced with more infantry, some artillery, and one company of L-3 tankettes. The town was heavily fortified with a large number of stone and concrete bunkers surrounded by barbed wire entanglements and covered by a well organised fire plan. The partisan attack began on the evening of 15 February but failed.
After reinforcement, the 3rd Assault Division made another attempt, and this succeeded. The Italian garrison was destroyed, 120 men killed and 220 captured. The partisans also captured four 100-mm (3.94-in) howitzers, two 47-mm anti-tank guns, nine 81-mm (3.2-in) mortars, 12 heavy machine guns and 25 light machine guns. All of the Italian tankettes were captured or destroyed: nine were captured in the Prozor area, and two were captured later in Ostrozac, and all 11 of these vehicles were used for the establishment of the Tank Company of the Supreme Command. The Italian reinforcements despatched earlier on that day were also destroyed: the 1/260o Reggimento near Dreznica, and one company of the 1/259o Reggimento, sent from Konjic, near Prozor.
The partisan offensive continued with the 10th 'Herzegovina' Brigade of the 3rd Assault Division attacking and routing a company of the 1/259o Reggimento in Rama on 20 February, inflicting losses of 183 killed and 7 captured Italian soldiers. On 22 February, the 5th Proletarian Brigade of the same division captured Ostrozac on the Neretva river.
Meanwhile the 4th Proletarian Brigade of the right-hand column captured a further 270 Italians, 140 of them in the town of Jablanica, which was taken on 22 February. Among the captured were Tenente Colonnello Pelleroni, commander of the Jablanica garrison, and Colonnello Malantonio, commander of the 259o Reggimento. Malantonio was shot after the partisans had established that he was a prominent member of the fascist party, and that he had taken part in the Spanish Civil War as an officer in the Italian Corpo Truppe Volontarie. With the fall of Jablanica, the partisans were in control of the whole of the Neretva river valley between Mostar and the Ivan sedlo pass; only the strategically important town of Konjic was still in Italian hands.
The left-hand column had achieved only partial concentration, but nonetheless decided to proceed with the plan using only two of its three brigades. The main objectives on the railway lin e linking Sarajevo and Konjic, the Ivan sedlo pass and Rastelica, were defended by the Ustase Railway Battalion, and significant targets on the railway line were Bradina, Lukač and Brđani, which were defended by Italian units, of up to company strength, in strong positions. The 1st Proletarian Brigade captured the important Ivan sedlo mountain pass and Raztelica station on 17 February by coup de main assault. The Italian positions fell on 18 February, after exchanges of artillery and mortar fire, after an attempted intervention by an armoured train from Konjic had been beaten. In that situation. The headquarters of the 1st Proletarian Brigade now made a critical error in judgement by sending two battalions to attack the railway station at Tarčin near Sarajevo, and its other two battalions on a surprise attack on Konjic, thus leaving the most important objective in its area, the Ivan sedlo mountain pass, virtually unoccupied.
The surprise raid on Konjic was conceived as an attempt to exploit Italian demoralisation and in the hope of establishing contact with the 3rd Assault Division’s 5th 'Montenegro' Brigade for a joint attack. The two units did not link, however, and during the night of 19/20 February, two battalions of the 1st Proletarian Brigade delivered an unsupported attack on Konjic, the main target of the entire partisan undertaking. After making some initial success, the Italian defenders were thrown back from the right bank of the river. However, since only two partisan companies managed to cross the river and reach the centre of the town, they were easily halted by heavy mortar and artillery fire. At dawn, appreciating that no progress was being made, the brigade’s headquarters cancelled the attack.
The other two of the brigade’s battalions attacked Tarčin on the night of 20/21 February, but this partisan effort coincided with the arrival of the German reinforcements from Sarajevo. The partisans were outnumbered, and the Germans drove them back and resumed their movement toward the Ivan sedlo pass. The appearance of German units in Tarčin marked the beginning of the so-called 'Weiss Mostar' operation.
In this, by the third week in February the partisans had managed to breach the Italian blockade along the Neretva river, thereby threatening one of the main objects of 'Weiss II'. Worse, from the Axis point of view, was the fact that the partisans took captured Posusje and endangered the wider Mostar area, which provided the German war industry with 10% of its bauxite ore requirements. As Italian troops appeared incapable of containing the situation, the German command had to adjust the operational plan: it decided to make an immediate deployment of the 718th Division to the endangered areas before the launch of 'Weiss II'.
The 718th Division started its attack on 19 February: one column advanced from Bugojno toward Gornji Vakuf and Prozor, and the other from Sarajevo toward Konjic. Jablanica was the ultimate objective of these two pincer arms. The column from Bugojno was the Kampfgruppe 'Vogel' and comprised the 738th Regiment less one battalion, the Ustase 5th Brigade (the so-called Black Legion) and artillery. It captured Gornji Vakuf on 22 February, and then found itself stuck in a 10-day battle against the reinforced 7th 'Banija' Division in front of Prozor.
The column from Sarajevo was the Kampfgruppe 'Annacker' and comprised the ]e]750th Regiment less one battalion, two battalions of the 7th Home Guard Regiment, one Ustase battalion, artillery and one platoon of tanks. This Kampfgruppe fell on two battalions of the 1st Proletarian Brigade in Tarčin on 21 February. The Kampfgruppe repulsed the partisan attack on Tarčin, drove back several partisan battalions, and on the same day reached the Ivan sedlo pass and Rastelica. The partisans then regrouped and on the following day retook their positions on the Ivan sedlo pass, but a substantial part of the Kampfgruppe 'Anneker', including single German and Croat battalions, an Ustase company, and a number of tanks, succeeded in breaking through to Konjic on 22 February. They arrived just in time to effect a decisive strengthening of the garrison before a major partisan attack. The commander of the 1st Proletarian Brigade, Colonel Danilo Lekić-Spanac, had to answer in person to Tito for the failure of his brigade to seal the approaches to the lower reaches of the Neretva river valley.
The fact that Konjic controlled the only road leading to the eastern part of Herzegovina (the rest of the eastern bank of the Neretva river to the south of the town being dominated by the virtually impassable Prenj mountain), made it the prime objective of the partisan army. The garrison of Konjicwas at first the 1259th Regiment with artillery elements and other units. During the fighting at Prozor, Rama and Jablanica, parts of Konjic’s garrison had been despatched as reinforcement, and had been destroyed. The 154a Divisione da occupazione 'Murge' in a single week suffered losses of some 2,300 men, and was so demoralised that an element of panic became evident, which created great optimism among the partisans. Immediately before the main partisan attack, however, an Axis force of 2.5 battalions, the vanguard of the Kampfgruppe 'Annaker', entered the town. At the same time, some 3,000 Četniks under the command of Major Vojislav Lukačević reached the town, and agreed with the garrison that they would assume positions around the town. Thus Konjic unexpectedly became a very difficult obstacle for the whole of the Main Operational Group.
The 3rd Assault Division decided to storm the town using two of its brigades (the third remained in Prozor), with the 5th 'Montenegro' Brigade attacking along the right bank of the river, and the 10th 'Herzegovina' Brigade along the left bank. The hastily organised attack began during the evening of 22 February. For lack of adequate intelligence, the 10th 'Herzegovina' Brigade ran into strong Četnik resistance on the eastern bank and could barely reach the town before dawn. On the opposite bank, the 5th 'Montenegro' Brigade faced stiff resistance by German and Italian units and achieved little. As a result, by the morning of 23 February the 3rd Assault Division saw no alternative but to cancel the attack.
For the next attempt, during the evening of the following day, the attacking forces were reinforced with the 4th 'Montenegro' Brigade of the 2nd Proletarian Division and the Tank Company of the Supreme Headquarters. The attack continued through the night and resumed on the next night, but to no avail.
As the blockade of the Ivan sedlo pass by the 1st Proletarian Division seemed to be holding, and no further parts of the Kampfgruppe 'Annaker' reached Konjic, Tito decided to commit another brigade, and at a time early on 26 February, the 3rd 'Krajina' Brigade left its positions around Prozor and began its march to the embattled town. After only a few hours, though, the brigade was recalled as the appearance of the 717th Division, which was now assaulting Prozor instead of Livno, as had originally been envisaged by the plan for 'Weiss II, on the flank of the 'Kampfgruppe 'Vogel' endangered the whole of the partisans' western front and directly exposed the Central Hospital to the German attack. Thus the attack on Konjic, using additional forces from the Prozor area, had to be cancelled.
At this stage, Tito and his headquarters suddenly found themselves facing an entirely different situation from that which they had faced only a matter of days earlier. By 20 February the prospects had seemed good for the Main Operational Group as all but one Italian garrison in the Neretva river valley had been destroyed and the road to eastern Herzegovina appeared to be open. Now, the road was blocked by unexpectedly strong resistance in Konjic, and the partisan forces were hemmed in the narrow Neretva river valley and surrounded on all sides by strong Axis forces. On 25 February the Germans launched 'Weiss II' with attacks by two divisions on Drvar, Glamoč and Livno; the Italians in Mostar regrouped, and fielded two battle groups with Četnik support up the river; and more strong Četnik concentrations were detected on the eastern bank of the Neretva river. The partisan plan had therefore to be revised, and several difficult decisions had to be made.
Based on all available intelligence, the German command had concluded that Livno was the core of the south-eastern half of the partisan-controlled territory. For that reason, 'Weiss II' had been schemed as a concentric attack on Livno, with the assumption that the partisans would be driven back, encircled and destroyed there. In the meantime, the situation had changed. The partisans had broken into the Neretva river valley, and their main concentration was now between Prozor and Konjic. Despite this, the German command proceeded largely with the original plan. In light of the recent developments, however, the 718th Division and one week later the 717th Division were directed to the new decisive point.
The 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen' and the 369th Division were used for 'Weiss II'. The two formations began their advance on 25 February. The route assigned to the 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen' was from Bosanski Petrovac, past Drvar and Bosansko Grahovo, to Livno, while the 369th Division had to cover the route from Mrkonjić-Grad past Mlinista and Glamoč to Livno. In front of the German divisions were six out of the 10 brigades of the partisans' I Bosnian Corps, whose headquarters planned no decisive defence. The partisan forces were therefore to put up just enough resistance to allow the units and the civilian population to be evacuated, and thereafter evade rather than fight the Germans' advancing columns. The 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen' captured Drvar on 28 February, and continued in the direction of Grahovo, pushing back the 8th, 9th and 10th 'Krajina' Brigades. On the road to Glamoč, the 4th and 7th Krajina Brigades were slowing the 369th Division. As the 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen' reached Grahovo, and the 369th Division took Glamoč on 2 March, the corps headquarters decided to shift to the evasion part of the overall plan, and the brigades, together with a mass of the refugees, began to move over Sator mountain toward Rore and back to the Krajina. In sub-zero temperatures and deep snow, the march over the high mountain area cost many civilian their lives. The Germans made great efforts to pursue the partisans through the mountain, but the latter were elusive, and the only result was the capture of a number of exhausted refugees.
After this manoeuvre, most of the I Bosnian Corps ' formations and units were out of reach of the advancing Germans, the exceptions being the 7th and 9th 'Krajina' Brigades. These were temporarily subordinated directly to the partisans' supreme headquarters, which had ordered them to slow the German advance toward the Neretva river. On 5 March, the two German divisions had finally reached Livno and taken it without a fight. After several days of rest, the 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen' resumed its movements to the Mostar bauxite area without partisan interference and the 369th Division moved toward Jablanica.
Farther to the south, the group of Herzegovina Četnik units under Lieutenant Colonel Petar Baćović was marching from Split toward the Neretva river area. This group had been transported by the Italians by land and sea to Knin in December 1942 in order to fight the partisan forces in Lika. Early in February 1943, the group was first returned to Split and then ordered to make an overland march to the Neretva river area. While passing through the Biokovo hinterland, the group committed numerous crimes against the civilian population. Around Vrgorac, the group encountered the elements of the partisans' 9th 'Dalmatia' Division. This latter was deployed in the broader area of Imotski, and was already under pressure from the east by the Italian Gruppo di battaglia reggimentale 'Scotti' from Mostar and from the south-east by Montenegtin Četniks under Major Andrija Vesković from Ljubuski. In the fsace of these decidedly unfavourable odds, the division had little option but to retreat toward Jablanica, where it became a part of the Main Operational Group.
In the last days of February, the Main Operational Group found itself in a critical position with no road available to it. On the one side it was pinned in front of the stubborn defence of Konjic’s garrison, and on the other it was exposed to the mounting pressure on Prozor. There was also constant pressure from the reinforced parts of the 718th Division from Sarajevo, increasing pressure of the Italian and Četnik battle groups from Mostar, the concentration of more Četnik forces on the eastern bank of the Neretva river, and the eastward progress of the 7th SS Freiwilligen Gebirgsdivision 'Prinz Eugen' and the 369th Division. Moreover, alarming news about the imminent threat faced by the Central Hospital was reaching Tito’s HQ on a daily basis.
In this situation, Tito assumed operational command, and on 28 February decided to reverse the direction of the attack, and, instead of pushing over the Neretva river, to strike hard at the Germans exerting pressure on Prozor. According to this new direction, Tito ordered His pioneer company to destroy all the bridges across the Neretva river, a task completed between 1 and 4 March. He also ordered all the forces to concentrate their attacks against Gornji Vakuf, with only necessary rearguards left on the Neretva river.
The partisan counterattack began only just in time to avert a possible disaster. the 717th Division and the Kampfgruppe 'Vogel' were attacking along the road linking Gornji Vakuf and Prozor with their main column, while trying at the same time to outflank the partisan defence with flanking columns over Pidris and Vilića Gumno, intending to capture the important pass at Makljen. At dawn on 2 March, the 4th Proletarian Brigade, led by its 2nd Battalion, bypassed the columns of wounded from the Central Hospital, reached Vilića Gumno, and took position position in the deep snow, 100 to 150 ft (30 to 50 m) from the German lines, and was almost immediately attacked by the 749th Regiment. After several hours, the brigade charged the German positions and pushed their men back down the slopes of the Radusa mountain. The fighting was intense and undertaken under notably difficult circumstances, and the losses were serious. The German report for that day counted 51 men killed, 83 wounded and 21 missing as well as 31 cases of frostbite. On the other side, the 3rd Company of the 2nd Battalion fell to just eight men.
During 2 and 3 March, more partisan brigades reached Prozor and took up positions. On 4 March, a major partisan counterattack was launched by all nine available brigades: five delivered a frontal assault on the German positions, and the other four tried to outflank the German positions. The Germans were driven back all the way to an area near Bugojno, where they waited and prepared defensive positions until 8 March. In the fight on 4 March the 2nd Proletarian Brigade captured Major Arthur Strecker, commander of the 3/738th Regiment, and in the following days used him to propose to the Germans a prisoner exchange and talks on some other subjects to the Germans. This led to the famous 'March negotiations'.
The German command was both confused and concerned about the success of the partisan attack at Gornji Vakuf. On the assumption that the partisans would continue their advance toward Bugojno, Lüters ordered the 369th Division to the area on 6 March. Tito was not happy with the prospects of the advance/retreat to the Vrbas river valley, for he feared that the partisans would thus merely exchange one cauldron for another. In light of these considerations, and much to the surprise of his closest associates, Tito ordered a 180° turn to take the main weight of his forces back to the Neretva river.
The key role in forcing the Neretva river fell to the 2nd 'Dalmatia' Brigade. During the preparations for Gornji Vakuf counterattack, the brigade had been left on the Neretva river as a rearguard. After the counterattack had been launched, the brigade commander, Major Ljubo Vučković, did not consider the possibility of any return to the river, and therefore ordered the evacuation of Jablanica, deploying his unit in the hills outside the town. However, on 4 March, Tito called summoned Vučković to a meeting, criticised him for the abandonment of Jablanica, and ordered him to complete the immediate reoccupation of the town. Vučković was also instructed to cross the Neretva river with his unit in the course of the following night, clear the Četniks from the eastern bank, and secure a bridgehead.
The reoccupation of Jablanica was easier than had been feared. As the Tank Company of the Supreme Headquarters was available, it was became the spearhead of the attack on the town, which was held by two battalions of the Četnik 'Durmitor' Brigade. Seeing the advancing tankettes, the Četniks assumed that these were the van of the Italian relief column, and moved out to meet them. The partisans seized the opportunity presented by the Četnik confusion and opened fire, causing the Četniks to panic and decamp. The 2nd 'Dalmatia' Brigade spent the rest of the day in the assessment of a numb er of options for crossing the river. Since the pioneer detachment did not arrive until a time late in the evening, Vučković informed the supreme command that it would be impossible to cross the Neretva river during the same night. On the following day, 6 March, the brigade was reinforced by the 2nd Proletarian Brigade. Under the cover of darkness, one group of 12 men from the 2nd Company of the 3/2nd 'Dalmatia' Brigade crossed the skeleton of the demolished railway bridge and began to climb the steep eastern bank. The Četniks holding the bunker above the bridge sensed something was afoot and began firing blindly, killing two of the partisan group. The other 10 men reached the top of the cliff and destroyed the bunker with hand grenades. Once this obstacle was out of the way, the rest of the battalion followed, and after it two battalions of the 2nd Proletarian Brigade. On the following day, these three battalions scattered the Četnik 'Durmitor' Brigade, its men fleeing deep into the rear, where they spread panic among other Četnik units. With this success, the bridgehead was secured, and the pioneers started their work on the construction of a new and improvised bridge resting on the skeleton of the old structure.
Tito’s new plan was to push the Germans back from Prozor and thus win both space and breathing room, and then to cross the Neretva river at Jablanica as quickly as possible. No renewal of attacks on Konjic was envisaged, for rather than using the road running through Konjic, the bulk of the Main Operational Group, with the Central Hospital and other non-combat units, was now to cross the Prenj mountain range right across the river at Konjic. It was impossible to take along the tanks, trucks and heavier artillery, so these were dumped into the river. One of the necessary preconditions for this manoeuvre was the tight blockade of the town. After the 1st Proletarian Brigade had left the Ivan sedlo pass to take part in the Gornji Vakuf counterattack, the bulk of the 718th Division, together with its headquarters, reinforced the garrison at Konjic. These forces exerted pressure on the partisan rearguards during the first days of March, and ultimately succeeded in pushing them back across Neretvica, some 6 miles (10 km) to the west of the town. On 5 March, the commander of the 3rd Assault Division, Major Pero Ćetković, received an order to push the Germans back to the town, and isolate the garrison. In fighting between 5 and 9 March, the partisans retook Ostrozac and other positions on the Neretva river, driving the Germans back to their original positions.
The final push over the Neretva river had five elements: first, on the left flank the 3rd Assault Division was tasked blockading Konjic; second, in the centre the 2nd Proletarian Division, reinforced with the 1st Proletarian Brigade, was tasked to cross the northern slopes of Prenj, toward Glavatičevo and the Crvanj mountain to reach the upper reaches of the Neretva river at Ulog and Obalj; third, on the right. the 7th 'Banija' Division with its two brigades was tasked crossing the river at Jablanica, circumventing Prenj from the south, and blocking the road from Mostar at Zijemlje' fourth, the 1st Proletarian Division with the 7th 'Krajina' Brigade (replacing the 1st Proletarian Brigade) was to act as the rearguard, checking the German advance from Bugojno toward Jablanica, and securing the main crossing point; and fifth, the 9th 'Dalmatia' Division was tasked to deny the Axis forces all access to the Neretva river from the south and south-west.
In order to counter this strategic 'checkmate', Tito prepared an elaborate deception in which his pioneers were to demolish all of the river’s bridges.
When air reconnaissance brought this information to the German command, it concluded that the partisans were preparing a final dash north of their current position, along the west bank of the Neretva river, and had blown the main bridge to prevent desertion as well as attack by Četnik forces from the other side of the river. They thus began a troop redeployment to block the anticipated movement.
This redeployment gave the partisan engineers the time they needed to repair the main bridge and to eliminate the Četniks defending the river’s far bank. The Germans quickly established what was actually taking place, but were unable to correct their mistake and prepare a serious attack in time, because of their previous redeployment orders. With their rearguard fighting off an increasingly powerful German advance, the partisans crossed the river under intense aerial bombardment, but the mountain terrain prevented accurate destruction of the makeshift bridge. After the partisan escape had been completed, the weak bridge was finally rendered useless in order to prevent pursuit. The humiliating German strategic defeat was amplified by the fact that Tito was able to keep his well-known pledge not to leave behind the wounded.
The operation marked the peak of Četnik collaboration with the Axis foces.
In order to ensure the operation’s success, Draza Mihailović relocated from Montenegro to Kalinovik, where Lieutenant Colonel Zaharije Ostojić, commander of operations in Herzegovina, has his headquarters.
The Četniks would have been disarmed by Germans if they had succeeded against the partisans in 'Weiss' (ii).
By the end of March, the Germans claimed to have killed about 11,915 partisans, executed 616 and captured 2,506. The loss of the German forces were between 514 and 583 men killed, between 1,214 and 1,642 men wounded and between 145 and 158 men missing; the Italian losses were 1,605 men killed and 983 captured; the Croat losses were 126 men killed, 258 wounded and 218 missing; and the Četnik losses were between 2,000 and 3,000 men.
Despite their losses and the Axis tactical victory, the partisan formations had secured their command and the hospital, and were able to continue operations. In fact, once they reached the eastern parts of Bosnia and Herzegovina, the partisans had to face only the Četniks, and in turn almost entirely incapacitated them in the area to the west of the Drina river.
The next major German operation in Yugoslavia was 'Schwarz' (ii).