France
In the United States, we typically refer to the World War II invasion of France by Allied forces at the beaches of Normandy as D-Day. "D-day," is actually military jargon for the day any operation goes into action, and H-hour" is the hour at which the operation commences. "Operation Overlord," as the planned incursion of France was called, has become the all-time most famous "D-Day" of American military forces. The Allies were seeking to retake France, which had fallen under German control early in the war.
