What was the planned Allied invasion of Japan’s southern island Kyushu called in 1945?

Operation Olympic was the planned Allied invasion of Kyushu, Japan’s southernmost main island, in 1945.

Olympic was the first phase of Operation Downfall, the broader plan for invading the Japanese home islands. It was scheduled to begin on November 1, 1945, with landings on Kyushu. A second phase, Operation Coronet, was planned for Honshu near Tokyo in March 1946.

The plans were abandoned after Japan surrendered in August and formally signed the Instrument of Surrender on September 2. The anticipated invasion had nevertheless influenced Allied planning and Japanese defense preparations. Both sides expected enormous casualties if the operation occurred.

Operation Olympic should not be confused with Operation Coronet, which targeted Honshu, or Operation Neptune, the naval component of the 1944 Normandy invasion. The cancellation of Olympic is one reason the surrender period is often discussed alongside the projected invasion of Japan.