Prince Chichibu at maneuvers (photo)

Prince Chichibu at maneuvers; Prince Chichibu Yasuhito was subsequently appointed battalion commander of Thirty-First Infantry Regiment in August 1937; promoted to lieutenant colonel in 1938; and finally to colonel in August 1939. During the war, he was involved in combat operations, and was sent to Manchukuo before the Nomonhan incident and to Nanjing after the Nanjing massacre. Battle of Khalkhyn Golf (Mongolian: ?????? ????? ????????; Russian: ??? ?? ???? ??????-???; Japanese: ??????? Nomonhan jiken--i.e. Nomonhan Incident) was the decisive engagement of the undeclared Soviet-Japanese Border War, or Japanese-Soviet War, fought between the Soviet Union and the Empire of Japan in 1939. The battle was named after the river Khalkhyn Golf passing through the battlefield. In Japan, the battle was known as the Nomonhan Incident after a nearby village on the border between Mongolia and Manchuria.