What position did General Yoshijiro Umezu hold when he signed Japan's surrender document?

General Yoshijiro Umezu was Chief of the Army General Staff when he signed Japan's surrender document.

Umezu signed the Japanese Instrument of Surrender after Foreign Minister Mamoru Shigemitsu. His signature was made “by command and in behalf of the Japanese Imperial General Headquarters,” representing Japan's military command rather than its civilian government.

Umezu had become Chief of the Army General Staff in 1944 and remained in that position through the final months of the war. He was one of the senior officers involved in Japan's wartime decision-making and was initially opposed to accepting the Potsdam Declaration without stronger guarantees.

The role is easy to confuse with the position of War Minister, which was held by General Korechika Anami during the final surrender crisis. Umezu's presence at the ceremony showed that both the Japanese government and the Imperial General Headquarters were formally bound by the surrender.