Allied invasion of northern Europe in World War II that began on June 6, 1944, with the largest amphibious landing in history in Normandy, France.
Also called Operation Overlord, the landing transported 156,000 U.S., British, and Canadian troops across the English Channel in over 5,000 ships and 10,000 planes. Commanded by Gen. Dwight D. Eisenhower , the Allied forces landed at five beaches on the Normandy coast and soon established lodgement areas, despite stiff German resistance and heavy losses at the code-named Omaha Beach and Juno Beach. Allied air supremacy prevented rapid German reinforcements, and discord between Adolf Hitler and his generals stalled crucial counterattacks. Though delayed by heavy fighting near Cherbourg and around Caen, the Allied ground troops broke out of the beachheads in mid-July and began a rapid advance across northern France. The Normandy Campaign is traditionally considered to have concluded with the liberation of Paris on Aug. 25, 1944.