What 1956 agreement ended the state of war between Japan and the Soviet Union after World War II?

The Soviet–Japanese Joint Declaration of 1956 ended the state of war between Japan and the Soviet Union.

Japan and the Soviet Union signed the declaration in Moscow on 19 October 1956, and it entered into force on 12 December 1956. The agreement restored diplomatic relations and formally ended the state of war that had continued between the two countries after the 1945 fighting.

The Soviet Union had not signed the 1951 Treaty of Peace with Japan, commonly called the Treaty of San Francisco. As a result, Japan and the Soviet Union still lacked a peace treaty even though Japan had surrendered to the broader Allied coalition in 1945.

The declaration also addressed future negotiations over a peace treaty and included a Soviet pledge concerning the Habomai Islands and Shikotan. The territorial issue remained unresolved, so the 1956 agreement normalized relations without producing a final peace treaty.