Which 1951 peace treaty, effective in 1952, ended the legal state of war between Japan and most Allied nations?

The Treaty of San Francisco, effective in 1952, ended the legal state of war between Japan and most Allied nations.

The treaty was signed on 8 September 1951 at the War Memorial Opera House in San Francisco and came into force on 28 April 1952. Its formal title was the Treaty of Peace with Japan. Japan signed with 48 Allied nations, although not every wartime Allied power participated in the settlement.

The treaty ended the Allied occupation of Japan, restored Japanese sovereignty and required Japan to accept the judgments of Allied war-crimes tribunals. It also established the legal framework for Japan’s postwar international position.

The treaty is distinct from the 1945 Japanese Instrument of Surrender. The surrender document ended the fighting and established the occupation, while the San Francisco treaty later created a formal peace settlement. The Soviet Union attended the conference but did not sign the treaty. China was also excluded because of disagreement over whether the Republic of China or the People’s Republic of China represented China.