The German invasion of the Soviet Union in the summer of 1941 marked a fundamental change in both the scope and systematic nature of Nazi mass violence. Over the course of the next three years, German warfare and rule in the occupied Soviet territories caused death and suffering on an unprecedented scale. It is particularly the death toll among civilians and other non-combatants that stands out here. The majority of Soviet war dead comprised civilians and unarmed, captured soldiers. In deliberate policies of mass murder, German forces killed 3.3 million Soviet prisoners of war, 2.6 million Jews, more than 2 million residents of Soviet cities, 30,000 Roma, at least 17,000 psychiatric patients, and up to 600,000 rural-dwelling civilians in so-called anti-partisan operations. The military operations of the German-Soviet War cannot be addressed independently of mass murder in this theatre, where 10 million Wehrmacht soldiers were stationed at one time or another between 1941 and 1944. The number of Wehrmacht divisions deployed on the Eastern Front in which no war crimes were committed was low, and members of the Wehrmacht may indeed have made up the majority of those responsible for large-scale crimes committed here by the German Reich.