Which 1945 Allied ultimatum demanded Japan’s unconditional surrender before V-J Day?

The Potsdam Declaration was the 1945 Allied ultimatum that demanded Japan’s unconditional surrender before V-J Day.

The declaration was issued on July 26, 1945, by the United States, the United Kingdom, and China. It warned Japan that rejection would bring “prompt and utter destruction” and called for the unconditional surrender of the Japanese armed forces. The Soviet Union did not sign the original declaration because it was not yet at war with Japan.

The document also outlined broad postwar conditions. Japan’s sovereignty would be limited to the home islands and other islands determined by the Allies, Japanese militarism would be eliminated, and the country would be occupied until peaceful and democratic institutions were established.

Japan initially rejected the declaration publicly, using the term mokusatsu, often translated as ignoring or withholding comment. After the atomic bombings and the Soviet declaration of war, Japan accepted the Allied terms in August. The surrender document signed on September 2 expressly referred to the Potsdam Declaration as the basis for Japan’s capitulation.