What was the first official U.S. military order issued to Japan after its surrender?

General Order No. 1 was the first official U.S. military order issued to Japan after its surrender.

The order was prepared by the United States Joint Chiefs of Staff and approved by President Harry S. Truman on August 17, 1945. General Douglas MacArthur issued it to Japan after the surrender, and Japanese Imperial General Headquarters transmitted it to Japanese forces on September 2.

General Order No. 1 directed Japanese forces to surrender to designated Allied commanders. It required them to reveal military deployments, preserve equipment, and follow instructions connected with disarmament and occupation. It also divided responsibility for receiving Japanese surrenders across different parts of the former Japanese empire.

One important consequence concerned Korea. Japanese forces north of the 38th parallel were ordered to surrender to Soviet forces, while those south of the line surrendered to U.S. forces. The order therefore helped establish an occupation boundary that later became central to the division of Korea.