What was the Allied ultimatum that demanded Japan’s surrender in July 1945?

The Potsdam Declaration was the Allied ultimatum that demanded Japan’s surrender in July 1945. The United States, United Kingdom, and China issued it on July 26 at the Potsdam Conference.

The declaration called for the unconditional surrender of all Japanese armed forces and warned that refusal would bring “prompt and utter destruction.” It also outlined plans for disarmament, occupation, and the removal of militarist influence.

Japan’s government initially rejected or did not accept the declaration publicly. After the atomic bombings, the Soviet declaration of war, and internal political debate, Japan accepted its terms in August.

The declaration did not directly state what would happen to Emperor Hirohito. That omission became an important issue during surrender negotiations, since preserving the imperial institution mattered greatly to Japanese leaders.