How did the d day invasion contribute to the Allies victory in ww2?

Answer 1

It created the nightmare the German High Command always feared! Having to fight on 3 fronts, if you include the Italian front. The success at Normany, would forever during the rest of the war, pin down precious German manpower and tanks, at a time when the Soviet were getting stronger and destroying more German divisions then could ever been replaced. The Germans after D-Day, had to transfer valuable formations from Itay to meet the Allied threat in Southern France that summer of 1944. One of the great mysteries of the war, was why the Germans didn't take their forces out of Norway(there were 330,000), and shore up their defense either in the east or in France. They stayed in Norway till the end of the war. Hitler was alone in thinking that the British would invade Norway, which they never did.

Answer 2

D-Day was the first foothold on the coast of Europe. The troops and weapons landed that day opened the way to massive troop and tank landings over the next few weeks.