1941-1942: Einsatzgruppen and the decision for genocide

When Germany invaded the USSR in 1941, mobile killing squads called Einsatzgruppen followed the army. They rounded up Jews, communists, and other targets and shot them in mass graves. The mass shooting at Babi Yar near Kyiv in September 1941 killed about 33,000 Jews in two days. By the end of 1941, the Einsatzgruppen had killed over a million Jews and other targets in the East.

Nazi leadership concluded that mass shootings were inefficient and psychologically damaging to the killers. At the Wannsee Conference (January 1942), senior Nazi officials coordinated the "Final Solution": systematic extermination of European Jews through industrial death camps.