Several different days in military history were named D-Day. However, the most famous D-Day was the Normandy landings during Operation Overlord. This was on the morning of June 6, 1944, when the largest naval attack in military history took place. It was in France during World War II. "Operation Overlord was" led by American General Dwight D. Eisenhower. The Allies (Britain, Canada, and America in this case), breached the Normandy coastline. They broke through the German fortification chain, the Atlantic Wall. It was a turning point in World War II, though over 3,500 men were lost. 