What was the codename for the first stage of the planned Allied invasion of Japan?

Operation Olympic was the codename for the first stage of the planned Allied invasion of Japan.

Olympic was scheduled to begin in November 1945 and aimed to seize southern Kyushu, Japan’s southernmost main island. Allied planners intended to use Okinawa, already captured in 1945, as a major staging area for the operation.

The second stage of the overall plan was Operation Coronet, scheduled for spring 1946. Coronet would have targeted the Kanto Plain near Tokyo on Honshu. Together, Olympic and Coronet made up Operation Downfall.

Japan surrendered before either stage began. The projected invasion never took place, so later casualty estimates describe a possible campaign rather than actual losses. The Japanese military had anticipated a Kyushu landing and prepared Operation Ketsugō to defend the island.