Operation Olympic was intended to invade Kyūshū, Japan's southernmost main island.
Olympic was the first phase of Operation Downfall, the proposed Allied invasion of the Japanese home islands. Planners scheduled it to begin on November 1, 1945, with landings aimed at the southern third of Kyūshū. Okinawa was expected to serve as a staging base for the assault.
The planned operation included landings near Miyazaki, Ariake, and Kushikino. Captured territory and airfields on Kyūshū would support the later phase, Operation Coronet, which was planned for the Kantō Plain on Honshū near Tokyo. Japan prepared its own defense plan, Operation Ketsugō, against the expected invasion.
Olympic never took place. Japan's surrender in August followed the atomic bombings of Hiroshima and Nagasaki and the Soviet Union's entry into the war. Because the invasion was canceled, casualty estimates for it remain projections rather than actual battlefield totals.