Of the up to eighteen million men who served in the Wehrmacht during the Second World War, ten million were deployed at one time or another between 1941 and 1944 in the conflict against the Soviet Union, a theatre of widespread and sustained mass violence. In order to determine how extensive complicity in Nazi crimes was among the mass of the regular German soldiers, it is necessary first of all to define what constitutes a criminal undertaking. The sheer brutality of the German conduct of war and occupation in the Soviet Union has overshadowed many activities that would otherwise be rightly held up as criminal acts.