What was the code name for the planned Allied invasion of southern Kyūshū in November 1945?

Operation Olympic was the code name for the planned Allied invasion of southern Kyūshū in November 1945.

Olympic was the first stage of Operation Downfall, the proposed invasion of Japan’s home islands. Its scheduled X-Day was 1 November 1945. The objective was to seize the southern part of Kyūshū and establish bases for the later invasion of Honshū.

The second stage, Operation Coronet, was planned for the Kantō Plain near Tokyo and was tentatively scheduled for March 1946. Because Japan surrendered in August 1945, neither Olympic nor Coronet occurred. Operation Pastel, meanwhile, was a proposed deception plan connected with the invasion planning.

Some accounts also mention the alternate name Operation Majestic after the Olympic name was compromised through insecure communications. That later planning label does not change the fact that Operation Olympic was the principal code name for the Kyūshū invasion. The planned assault would have involved a huge naval and military force.