The "Allied Invasion" refers to the military operations conducted by the Allied forces during World War II to liberate occupied territories in Europe. The most notable operation was the D-Day invasion on June 6, 1944, when Allied troops landed on the beaches of Normandy, France. This marked a significant turning point in the war against Nazi Germany. The invasion involved extensive planning and coordination among the Allies, including the United States, United Kingdom, and Canada. It aimed to establish a foothold in Europe, allowing for further advances into German-occupied territories. The success of the invasion ultimately contributed to the defeat of the Axis powers.