Operation Olympic was the planned 1945 Allied attack on Kyushu, Japan’s southernmost main island.
Olympic formed the first stage of Operation Downfall, the proposed invasion of the Japanese home islands. The plan called for landings in southern Kyushu beginning on November 1, 1945, with Okinawa serving as a staging base. Capturing territory and airfields there would have supported a later invasion of the Tokyo region.
The operation was canceled after Japan surrendered in August 1945. Its cancellation prevented what planners expected to be a massive amphibious campaign involving large numbers of troops, ships, aircraft, and Japanese defenders. Estimates of casualties varied widely, and the debate over those estimates remains part of the historical discussion surrounding the end of the Pacific War.
Olympic is often confused with Operation Coronet, the second stage of Downfall. Coronet was intended for Honshu, particularly the Kanto Plain near Tokyo, in spring 1946. Neither invasion occurred because the surrender made the plans unnecessary.