Which Allied commander signed Japan's surrender on behalf of the Allied nations?

Douglas MacArthur signed Japan's surrender on behalf of the Allied nations.

MacArthur served as Supreme Commander for the Allied Powers and presided over the ceremony aboard USS Missouri on 2 September 1945. He signed the Instrument of Surrender first for the Allied powers, after Japanese Foreign Minister Mamoru Shigemitsu and General Yoshijiro Umezu had signed for Japan.

Fleet Admiral Chester Nimitz then signed as the United States representative. Representatives of eight other Allied countries followed, including China, the United Kingdom, the Soviet Union, Australia, Canada, France, the Netherlands, and New Zealand.

MacArthur had commanded major Allied operations in the Southwest Pacific and had returned to the Philippines in 1944 after promising, “I shall return.” His role at the surrender ceremony made him the public face of the transition from wartime command to Allied occupation.