Operation Olympic was the codename for the first planned stage of Operation Downfall, the proposed Allied invasion of Japan.
Olympic was scheduled to target southern Kyushu, Japan’s southernmost main island, with an intended landing date of November 1, 1945. Allied planners expected the operation to seize airfields and establish a base for later attacks and the larger invasion of Honshu.
The second stage was Operation Coronet, planned for the Kanto Plain near Tokyo in March 1946. Together, Olympic and Coronet formed the outline of Downfall. The invasion was never launched because Japan surrendered before the planned operations began.
Operation Olympic is sometimes confused with Coronet because both belonged to Downfall. It is also distinct from Operation Overlord, the Allied invasion of German-occupied Normandy in June 1944. The anticipated costs of invading Japan were a major factor in American wartime planning, though historians continue to debate how decisive that consideration was.