"Full victory, nothing less", those were General Dwight D. Eisenhower's orders to his troops before dawn on June 6, 1944. Under his command, an Allied armada of more than 5,300 ships and 11,000 aircraft crossed the English Channel as 156,000 American, British, and Canadian soldiers stormed five heavily fortified beaches along the coast of Normandy, France. American forces bore the brunt of the bloodiest fighting at Omaha Beach, where thousands of GIs fell in the first hours of the assault. Originally scheduled for June 4, the invasion had been delayed two days by brutal weather, forcing Eisenhower into one of the most consequential command decisions in military history. By nightfall, the Allies had secured a foothold in Nazi-occupied Western Europe, cracking open the western front that would bring Germany to unconditional surrender less than a year later. D-Day remains the defining proof that American military power and Allied coalition-building can reshape the fate of entire continents.