The Soviets captured or deported nearly 325,000 Soldiers and civilians after the dual German/Soviet invasion of Poland in Sep 1939 (and murdered another 100,000). But by August 1941, Stalin was desperate for soldiers to repel the German invasion of the Soviet Union. In conjunction with the nascent Polish Govt-in-exile in London, Stalin agreed to establish a “Polish Army of the East”. Stalin signed the order on 13 August 1941, and the Gen Wladyslaw Anders, a former cavalry brigade commander in 1939, was chosen for the army’s commander. The gulags and prisons across Siberia were combed for Poles still healthy enough to train and fight. By the end of 1941, Ander’s had 25,000 soldiers and 1000 officers training deep in Siberia, and were supported by about 60,000 “camp followers” (for lack of a better term).
Anders was the senior surviving Polish officer captured by the Soviets in 1939. On 14 Aug 1941, the day after the order was signed, Anders was released from the NKVD’s dreaded Lubyanka Prison, one of only a handful of human beings in history that ever walked back out of Lubyanka after being sentenced there.