Before dawn on June 22, 1941, just over 3 million German soldiers invaded the Soviet Union, beginning the biggest conflict in history fought along a single front. On any given day from June 1941 to May 1945, an average of 9 million troops were deployed by Germany and the Soviet Union on the eastern front. German soldiers pushed twelve hundred miles from Poland to Moscow in a little over two months, and then for the next three and a half years fought through retreats, new offensives, sieges, and further retreats, finally being pushed back fifteen hundred miles to Berlin. Soviet losses were staggering: Between 20 and 27 million soldiers and civilians were killed. Germany lost 3 million soldiers, and in the final stage of the war, when the Soviets forced the battle onto German soil, 2.5 million German civilians were killed.

For German soldiers, going to war in the Soviet Union was a miserable...