How did the D-Day invasion and then the Allied

invasion of France affect Germany's strategy during World War II?

D-Day and the Allied invasion of France in June 1944 was a major strategic move in World War Two. It imposed a two-front war on Nazi Germany and its allies - the nightmare of German strategists - and gave some relief to the Soviet Union on the Eastern Front.

The Western Allies had promised to open a second front back in 1942 at the Casablanca summit, a major offensive move insistently urged by the USSR, which faced the bulk of German armies during WWII. With a Western Front now opened, Germany was forced to divide its dwindling forces and resources. Germany's strategic position significantly worsened and that accelerated its defeat.