The Imperial Japanese Army (IJA) (Kyūjitai: 大日本帝國陸軍, Shinjitai: 大日本帝国陸軍, Romaji: Dai-Nippon Teikoku Rikugun), or literally "army of the greater Japanese empire" was the official ground based armed force of Imperial Japan from 1871 to 1945. It was controlled by the Imperial Army General Staff Office and the Ministry of War, both of which were nominally subordinate to the Emperor of Japan as supreme commander of the army and the navy. Later an Inspectorate General of Military (Army) Aviation, became the third agency with oversight over the army. During wartime or national emergencies, the nominal command functions of the emperor would be centralized in an Imperial General Headquarters (IGHQ), an ad-hoc body consisting of the chief and vice chief of the Army General Staff, the minister of war