Imperial Japanese Army

The Imperial Japanese Army (IJA) was the official ground-based armed force of the Empire of Japan from its formation after the Meiji Restoration until 1945. It grew out of the Goshinpei guard raised from Satsuma, Chōshū and Tosa troops in 1871 and the regional garrisons (chindai). The Army Ministry was separated from the Ministry of Military Affairs in 1872 and the Conscription Ordinance of 1873 created a standing army based on universal male service. In 1878 the General Staff Office became independent of the ministry, establishing the "independence of the supreme command" directly under the Emperor. The Army Minister, Chief of the General Staff and Inspector General of Military Training were known as the "three chiefs". In 1888 the garrisons were reorganised into divisions, many based in former castle towns.

During the Meiji period, the IJA fought the Sino-Japanese and Russo-Japanese Wars and was responsible for constructing Japan's network of coastal fortifications, including the Yura Fortress system at Tomogashima, the Tokyo Bay Fortress, and numerous other defensive installations to protect Japan's major ports and cities from naval attack. In the Shōwa era the initiative of field armies repeatedly drove national policy: the Kwantung Army staged the Manchurian Incident in 1931, young officers launched the February 26 Incident in 1936, the rule that service ministers be active-duty officers was revived that year, and Imperial General Headquarters was set up after full-scale war with China began in 1937.

In the Pacific War the Army fought simultaneously in China, Southeast Asia and the Pacific islands. From seventeen standing divisions before the war it expanded to roughly five and a half million men by the surrender. Collapsing supply lines caused mass deaths from starvation and disease, and atrocities in occupied territories and POW camps — among them the Nanjing Massacre, the Burma–Thailand Railway and the Bataan Death March — were prosecuted at the Tokyo Trial and in Class B and C trials across Asia. Japan's Ministry of Health, Labour and Welfare counts about 2.3 million military and civilian-employee war dead for the army and navy together.

After the surrender the Army was disarmed and the Army Ministry was abolished on December 1, 1945, becoming the First Demobilization Ministry. Army sites on this website include division and regiment garrisons, schools, arsenals, airfields, fortress batteries and the underground works of 1944–45; many were reused after the war as schools, parks, or Self-Defense Force and U.S. bases.