4th Army (Yugoslavia)

4th Army
Armijski đeneral Petar Nedeljković commanded the Yugoslav 4th Army during the Axis invasion of Yugoslavia
Active	1941
Country	Kingdom of Yugoslavia
Branch	Royal Yugoslav Army
Type	Infantry
Size	Corps
Part of	1st Army Group
Engagements	Invasion of Yugoslavia
Disbanded	1941
Commanders
Notable commanders	Petar Nedeljković

The 4th Army was a Royal Yugoslav Army formation mobilised prior to the German-led Axis invasion of the Kingdom of Yugoslavia in April 1941 during World War II. It was drawn from the peacetime 4th Army District. When mobilised, it consisted of three divisions, a brigade-strength detachment, one horse cavalry regiment and one independent infantry regiment. It formed part of the 1st Army Group, and was responsible for defending a large section of the Yugoslav–Hungarian border, being deployed behind the Drava river between Varaždin and Slatina.

Despite concerns over a possible Axis invasion, orders for the general mobilisation of the Royal Yugoslav Army were not issued by the government until 3 April 1941, out of fear that this would offend Adolf Hitler and precipitate war. When the invasion commenced on 6 April, the 4th Army was only partially mobilised, and this weakness was exacerbated by fifth column activities within its major units and higher headquarters. Revolts of Croat soldiers broke out in all three divisions in the first few days, causing significant disruption to mobilisation and deployment. The town of Bjelovar was taken over by rebel troops. Widespread desertions of Croat troops, many of whom turned on their Serb comrades, made control even more difficult. German activity in the 4th Army sector in the first four days included limited objective attacks to seize crossings over the Mura and Drava rivers, along with air attacks by the Luftwaffe.