The First Czechoslovak Army in Slovakia was an ad-hoc military formation formed by the insurgents of the Slovak National Uprising (August – October 1944) against Nazi Germany.
[4]: 80 As the fortune of war on the Eastern Front turned against the Axis, Slovak soldiers began to desert in disproportionate numbers to the Red Army, especially after the widely acclaimed German defeat at the Battle of Stalingrad 1942/43.
On 28 August, the German government gave corresponding orders and received a token permission by Jozef Tiso, the puppet president of Slovakia.
Warnings were given out within the military resistance, and the Slovak National Uprising began on 29 August 1944, the same day as German troops moved to occupy the whole of Slovakia.
[7]: 502 In a protracted defensive battle, the Slovaks came under increasing pressure in mid-October 1944; a major German offensive of 18–20 October brought the military decision by enabling the capture of Banská Bystrica on the 27th.