Which four main Japanese islands were named in the Potsdam Declaration's sovereignty terms?

The Potsdam Declaration named Honshu, Hokkaido, Kyushu, and Shikoku as the four main Japanese islands whose sovereignty would remain central to postwar Japan.

The declaration stated that Japanese sovereignty would be limited to these islands and other minor islands determined by the Allies. This provision reflected the planned dismantling of Japan's wartime empire, including its control over Korea, Taiwan, and other territories acquired or occupied before and during the war.

The four islands are Japan's principal home islands. Honshu is the largest and includes Tokyo, Kyoto, and Hiroshima. Hokkaido lies to the north, Kyushu to the southwest, and Shikoku between Honshu and Kyushu. Okinawa was not one of the four islands listed in this specific clause.

The wording did not create a complete modern constitutional map on the day it was issued. Allied authorities later determined the status of surrounding islands and administered Japan during the occupation. The declaration nevertheless became a major framework for Japan's surrender and postwar territorial settlement.