Which Japanese military body did General Yoshijirō Umezu represent when he signed in 1945?

General Yoshijirō Umezu represented Japanese Imperial General Headquarters when he signed in 1945.

Umezu was Chief of the Army General Staff and signed the Japanese Instrument of Surrender after Foreign Minister Mamoru Shigemitsu had signed for the Japanese government. His signature therefore represented Japan’s military command rather than its civilian government.

The wording of the instrument identified Umezu as signing by command and on behalf of Japanese Imperial General Headquarters. This distinction is important because the ceremony included separate political and military representatives.

Umezu’s signature came at 9:06 a.m. Japan Standard Time on September 2, 1945. Douglas MacArthur accepted the surrender for the Allied Powers two minutes later, at 9:08 a.m.