Which document did the Allies require Japan to accept before its formal surrender in 1945?

The Allies required Japan to accept the Potsdam Declaration before its formal surrender in 1945.

Issued on July 26, 1945, the declaration was made by the United States, the United Kingdom, and China during the Potsdam Conference. It demanded the unconditional surrender of Japan’s armed forces and warned of “prompt and utter destruction” if Japan refused.

The declaration outlined major postwar conditions, including the disarmament of Japan, the punishment of war criminals, and the limitation of Japanese sovereignty to the home islands and other territories chosen by the Allies. It did not explicitly settle the future status of Emperor Hirohito, an omission that complicated Japanese decision-making.

Japan eventually accepted the declaration’s terms in August after the atomic bombings, the Soviet declaration of war, and intense internal debate. The acceptance was announced by Hirohito on August 15, while the formal surrender document was signed aboard USS Missouri on September 2.