The invasion of Nazi-occupied France was known as the Normandy landings or D-Day. It was a military operation that took place on June 6, 1944, during World War II, and was carried out by the Allied forces. The operation involved the landing of troops on the beaches of Normandy, France, with the objective of establishing a foothold on the continent and ultimately liberating Europe from Nazi control. The Normandy landings were a turning point in the war and marked the beginning of the end of Nazi Germany's grip on Europe.