What was the codename for the Allied invasion of Normandy on June 6, 1944?

Operation Overlord was the codename for the Allied invasion of Normandy on June 6, 1944.

The operation began with D-Day, when Allied forces landed on five Normandy beaches—Utah, Omaha, Gold, Juno, and Sword. Before the amphibious assault, roughly 1,200 aircraft carried out an airborne operation behind German lines. More than 5,000 vessels then supported the seaborne landings, creating a foothold in German-occupied France.

Operation Overlord was larger than the beach assault alone. Operation Neptune was the codename for the initial amphibious phase, while Overlord referred to the broader campaign to establish and expand the Allied lodgment in Normandy. This distinction causes a frequent mix-up: “D-Day” usually refers to June 6 itself, whereas the Battle of Normandy continued for weeks afterward.

The invasion opened a major western front against Nazi Germany. Allied forces broke out of Normandy in late July and August, helped liberate Paris, and advanced toward Germany. The campaign suffered heavy casualties, but it became a decisive turning point in World War II.