Which Allied commander signed Japan’s formal surrender as the senior Allied representative?

Douglas MacArthur signed Japan’s formal surrender as the senior Allied representative.

MacArthur was Supreme Commander for the Allied Powers and presided over the ceremony aboard the USS Missouri. He signed the Instrument of Surrender on behalf of the Allied nations, then Fleet Admiral Chester W. Nimitz signed as the United States representative.

MacArthur had commanded Allied forces in the Southwest Pacific Area and had returned to the Philippines in 1944 after withdrawing from the islands in 1942. His role at the ceremony connected the surrender with the long campaign to defeat Japan across the Pacific.

MacArthur also led the Allied occupation of Japan after the surrender. His headquarters supervised major political, legal, economic, and military reforms until the occupation ended in 1952. He was therefore both the principal Allied signer and the leading figure in Japan’s immediate postwar administration.