On June 6th, 1944, allied forces under the flags of Canada, the United Kingdom, and the United States landed on Juno, Sword, Gold, Utah, and Omaha beaches in Normandy in the largest landing invasion in history, paving the way for a western front to be opened in Europe during WW2.
Plus it's my birthday today, so I figured I'd ask!
I mean, a lot of fascists died and it was a huge blow to the third reich, and likely did shorten the war by at least a year, but at that point the direction of the war had already been settled. Germany lost their offensive edge into the Soviet Union and was actively being pushed back, and unless they somehow found a massive petroleum deposit underneath Frankfurt that nobody had noticed before, then the rest of the war would just be the Soviets making a long, protracted push towards Berlin as they did historically, just somewhat more difficult.
By summer of 1944, it was abundantly clear to everyone that Germany would lose this war, and opening up a second front in France was mostly there to curtail the very real possibility of spreading Soviet influence over Europe in the post war. By opening up their own front in the war, the West was really just ensuring they had more bargaining chips at the peace talks.