Who were the Einsatzgruppen?

The Einsatzgruppen were mobile killing units of the Nazi government during World War II. Their primary task was to carry out mass murder of Jews, prisoners of war, and other targeted groups in Eastern Europe. The Einsatzgruppen operated behind the front lines of the German army and were responsible for the mass shootings of civilians in occupied territories. Their actions were a key part of the Holocaust and resulted in the deaths of hundreds of thousands of people.