1940–1942 Red Army purges

Between October 1940 and February 1942, Joseph Stalin, the leader of the Soviet Union, ordered purges against the Red Army (against the Soviet Air Force in particular) and associated military-related industries. Many of those who were purged were made scapegoats to deflect blame of military losses the Soviets incurred during wartime, with some being forced to falsely admit guilt to crimes, often under torture.

Source: Wikipedia — 1940–1942 Red Army purges (CC BY-SA 4.0)