Which 1951 peace treaty ended the legal state of war between Japan and most Allied countries?

The Treaty of San Francisco ended the legal state of war between Japan and most Allied countries.

Also called the Treaty of Peace with Japan, it was signed on September 8, 1951, at the War Memorial Opera House in San Francisco. Japan and 48 Allied nations signed it, while several participating countries—including the Soviet Union—did not sign. The treaty entered into force on April 28, 1952.

Its implementation ended the Allied occupation of Japan and restored Japanese sovereignty. Japan also renounced claims to territories acquired through its prewar expansion, accepted responsibility for certain wartime judgments, and agreed to settle postwar issues through the treaty’s provisions.

The treaty did not by itself settle every relationship involving Japan. The People’s Republic of China and the Republic of China were not both represented at the San Francisco conference, so Japan later concluded a separate Treaty of Taipei with the Republic of China. The treaty is therefore distinct from the 1945 surrender instrument, which ended wartime hostilities but was not a permanent peace treaty.