Nine Allied governments signed Japan’s Instrument of Surrender aboard USS Missouri in 1945.
The signatories represented the United States, China, the United Kingdom, the Soviet Union, Australia, Canada, France, the Netherlands, and New Zealand. General Douglas MacArthur signed for the Allied powers, while Fleet Admiral Chester Nimitz signed for the United States.
The ceremony took place in Tokyo Bay on 2 September 1945. Japanese representatives signed first, followed by the Allied representatives. The instrument took effect at 9:25 a.m. Japan Standard Time, formally ending the war.
The number nine refers to Allied governments represented as signatories, not the number of Japanese delegates or the total number of ships present in Tokyo Bay. Those categories are often conflated when discussing the ceremony.