At what time did Mamoru Shigemitsu first sign Japan’s surrender instrument?

Mamoru Shigemitsu first signed Japan’s surrender instrument at 9:04 a.m. Japan Standard Time on September 2, 1945.

Shigemitsu signed on behalf of the Emperor and the Japanese government aboard USS Missouri in Tokyo Bay. General Yoshijirō Umezu followed at 9:06 a.m., signing for Imperial General Headquarters. The precise times are recorded in accounts of the ceremony and in the sequence of signatures on the document.

General Douglas MacArthur accepted the surrender at 9:08 a.m. Fleet Admiral Chester Nimitz then signed for the United States at 9:12 a.m. Representatives of seven other Allied powers followed in an arranged order.

The ceremony concluded at 9:25 a.m. JST, when the surrender formally took effect. Thus, 9:04 a.m. marks the first Japanese signature, not the beginning of the entire ceremony or the moment the war officially ended.