The 40th Infantry Division Slavonska was an infantry formation of the Royal Yugoslav Army that formed part of the 4th Army during the German-led Axis invasion of the Kingdom of Yugoslavia in April 1941. It was partly mobilised from the Osječka military district, and, like all Yugoslav infantry divisions of the time, was a very large and unwieldy formation which was almost entirely reliant on animal transport for mobility. Commanded by Brigadni đeneral Ratko Raketić, it was largely manned by Croat troops, many of whom saw the Germans as potential liberators from Serbian oppression during the interwar period, and the division also lacked modern arms and sufficient ammunition.
The preliminary attacks launched across the Drava by the Germans on 6 April were enough to spark revolts within the units of the division. One of its three infantry regiments rebelled the following day, and by 8 April the rebels had taken over Bjelovar. The division continued to disintegrate over the following days, then crumbled in the face of the combined arms assault of the 8th Panzer Division when it broke out of its bridgehead at Barcs on 10 April. A few mainly Serb remnants of the division continued to withdraw into Bosnia over the next week until a ceasefire was negotiated on 15 April. The Yugoslav Army surrendered on 18 April.
Background
The Kingdom of Serbs, Croats and Slovenes was created with the merger of Serbia, Montenegro and the South Slav-inhabited areas of Austria-Hungary on 1 December 1918, in the immediate aftermath of World War I. The Army of the Kingdom of Serbs, Croats and Slovenes was established to defend the new state. It was formed around the nucleus of the victorious Royal Serbian Army, as well as armed formations raised in regions formerly controlled by Austria-Hungary. Many former Austro-Hungarian officers and soldiers became members of the new army. From the beginning, much like other aspects of public life in the new kingdom, the army was dominated by ethnic Serbs, who saw it as a means by which to secure Serb political hegemony.
The army's development was hampered by the kingdom's poor economy, and this continued during the 1920s. In 1929, King Alexander changed the name of the country to the Kingdom of Yugoslavia, at which time the army was renamed the Royal Yugoslav Army (, VKJ). The army budget remained tight, and as tensions rose across Europe during the 1930s, it became difficult to secure weapons and munitions from other countries. Consequently, at the time World War II broke out in September 1939, the VKJ had several serious weaknesses, which included reliance on draught animals for transport, and the large size of its formations. Infantry divisions had a wartime strength of 26,000–27,000 men, as compared to contemporary British infantry divisions of half that strength. These characteristics resulted in slow, unwieldy formations, and the inadequate supply of arms and munitions meant that even the very large Yugoslav formations had low firepower. Generals better suited to the trench warfare of World War I were combined with an army that was neither equipped nor trained to resist the fast-moving combined arms approach used by the Germans in their invasions of Poland and France.
The weaknesses of the VKJ in strategy, structure, equipment, mobility and supply were exacerbated by serious ethnic disunity within Yugoslavia, resulting from two decades of Serb hegemony and the attendant lack of political legitimacy achieved by the central government. Attempts to address the disunity came too late to ensure that the VKJ was a cohesive force. Fifth column activity was also a serious concern, not only from the Croatian nationalist Ustaše but also from the country's Slovene and ethnic German minorities.
Structure
Peacetime organisation According to regulations issued by the VKJ in 1935, the headquarters of the 40th Infantry Division Slavonska (40th ID) would be created at the time of mobilisation. Unlike most other Yugoslav divisions, the 40th ID did not have a corresponding divisional district in peacetime, and would be allocated units from other divisional districts and the VKJ reserve when it was formed. The division was named for the region of Slavonia.
Wartime organisation
The wartime organisation of the VKJ was laid down by regulations issued in 1936–37, which set the strength of an infantry division at 26,000–27,000 men. A total of 11,200 horses and other pack and draught animals were required to provide mobility for each infantry division. The theoretical wartime organisation of a fully mobilised Yugoslav infantry division was: headquarters divisional infantry headquarters, with three or four infantry regiments divisional artillery headquarters, with one or two artillery regiments a cavalry battalion with two squadrons, a bicycle squadron and a machine gun platoon a pioneer battalion of three companies an anti-tank company, equipped with twelve or anti-tank guns a machine gun company an anti-aircraft machine gun company a signals company logistics units
Each infantry regiment was to consist of three to four infantry battalions, a machine gun company, and the divisional artillery regiments were animal-drawn and largely equipped with World War I-vintage pieces. An artillery regiment consisted of four battalions, one of light howitzers, one of or mountain guns, and two of or field guns. In September 1939, after the German invasion of Poland, the 40th ID underwent a trial mobilisation which included a large proportion of its units.
The 40th ID was included on the wartime order of battle in "Defence Plan S", which was developed by the Yugoslav General Staff in 1938–1939. It was to be formed using mainly Croat-manned units. These comprised the Bjelovar-based 42nd Infantry Regiment from the Osječka divisional district, and the 43rd and 108th Infantry Regiments and 40th Artillery Regiment from the VJK reserve.
Planned deployment
The 40th ID was a component of the 4th Army as part of the 1st Army Group, which was responsible for the defence of north and northwestern Yugoslavia. The 4th Army was to deploy in a cordon along the western sector of the Hungarian border, with the 40th ID opposite the Hungarian town of Barcs, between Kloštar Podravski and Čađavica, with the main line of defence along the northern slopes of the Bilogora mountain range, and divisional headquarters at Pivnica Slavonska. On the left flank of the division was the 27th Infantry Division Savska (27th ID) opposite the Hungarian village of Gyékényes, and on the right flank was the 17th Infantry Division Vrbaska (17th ID) of the 2nd Army, which formed part of the 2nd Army Group, with the boundary running from just east of Slatina through Požega towards Banja Luka. The only border guard unit in the division's area was the 2nd Battalion of the 393rd Reserve Regiment.
Operations
Mobilisation After unrelenting pressure from Adolf Hitler, Yugoslavia signed the Tripartite Pact on 25 March 1941. On 27 March, a military coup d'état overthrew the government that had signed the pact, and a new government was formed under the Royal Yugoslav Army Air Force commander, Armijski đeneral Dušan Simović. A general mobilisation was not called by the new government until 3 April 1941, out of fear of offending Hitler and thus precipitating war. However, on the same day as the coup Hitler issued Führer Directive 25 which called for Yugoslavia to be treated as a hostile state, and on 3 April, Führer Directive 26 was issued, detailing the plan of attack and command structure for the invasion, which was to commence on 6 April.
As the Axis invasion began, the 40th ID was partially mobilised, with some elements of the division still mobilising, some in concentration areas, and only a small proportion actually deployed in their planned positions: the divisional commander Brigadni đeneral Ratko Raketić and his headquarters staff were mobilising in Bjelovar the 42nd Infantry Regiment with two battalions was marching towards their positions near Daruvar, while the rest of the regiment was mobilising in Bjelovar and could not move due to lack of draught animals the 43rd Infantry Regiment, with about 75–80 percent of its troops and 30 percent of its animals, was marching from its mobilisation centre in Požega towards Našice, but had only reached Jakšić, northeast of Požega the 108th Infantry Regiment was marching from Bjelovar but had only reached Severin the 40th Artillery Regiment was still mobilising with the headquarters and one battalion in Osijek and two battalions in Varaždin the divisional cavalry battalion and machine gun battalion were unable to deploy from Virovitica due to lack of animals, although on 5 April, Nedeljković had requisitioned private cars for the machine gun battalion and ordered it to concentrate at Lukač northeast of Virovitica the remainder of the divisional units were at their mobilisation centres in and around Bjelovar
The 43rd Infantry Regiment was ordered to march east to join the 17th ID, which was part of the 2nd Army Group's 2nd Army. The 89th Infantry Regiment, originally allocated to the 17th ID, was ordered to march from its mobilisation location in Sisak and join the 40th ID to replace the 43rd Infantry Regiment. The divisional cavalry battalion did not receive sufficient horses, and had to deploy on foot as infantry. The division was without artillery support throughout the fighting because the 40th Artillery Regiment did not complete mobilisation.
6 April
German Army headquarters wanted to capture the bridges over the Drava intact, and from 1 April had issued orders to the 2nd Army of Generaloberst Maximilian von Weichs to conduct preliminary operations aimed at seizing the bridge at Barcs and the railway bridge northeast of Koprivnica by coup de main. As a result, limited objective attacks were launched along the line of the Drava by the XXXXVI Motorised Corps, commanded by General der Panzertruppe Heinrich von Vietinghoff, despite the fact that they were not expected to launch offensive operations until 10 April. During the day, the Luftwaffe (German Air Force) bombed and strafed Yugoslav positions and troops on the march, and by the evening it had become clear to the Germans that the Yugoslavs would not be resisting stubbornly at the border. XXXXVI Motorised Corps was then ordered to begin seizing bridges over the Drava, including at Barcs. The local attacks were sufficient to inflame dissent among the Croat troops of the 4th Army, who refused to resist Germans they considered their liberators from Serbian oppression during the interwar period.
The continuing mobilisation and concentration of the 4th Army was hampered by escalating fifth column activities and propaganda fomented by the Ustaše. Some units stopped mobilising, or began returning to their mobilisation centres from their concentration areas. The Yugoslav radio network linking the division with the 4th Army and flanking divisions was sabotaged by the Ustaše on 6 April, and radio communications within the 4th Army remained poor throughout the fighting.
7 April About 19:00 on 7 April, German units in regimental strength with a few tanks began to cross the Drava near Barcs in the divisional sector. They quickly overcame the resistance of the 2nd Battalion of the 393rd Reserve Regiment, which was influenced by Ustaše propaganda. The border guards abandoned their positions and weapons and retreated to Virovitica. The 108th Infantry Regiment of the division had mobilised in Bjelovar and on 7 April was marching towards Virovitica to take up positions. That night, Croat members of the regiment revolted, arresting the Serb officers, non-commissioned officers and soldiers. The regiment then marched back to Bjelovar, where it joined up with other rebellious units about noon on 8 April.