Initially, the Army Ministry was in charge of both administration and operational command of the Imperial Japanese Army; however, from December 1878, the Imperial Army General Staff Office took over all operational control of the Army, leaving the Army Ministry only with administrative functions.
The Imperial Army General Staff was thus responsible for the preparation of war plans; the military training and employment of combined arms; military intelligence; the direction of troop maneuvers; troop deployments; and the compilation of field service military regulations, military histories, and cartography.
The Chief of the Army General Staff was the senior ranking uniformed officer in the Imperial Japanese Army and enjoyed, along with the War Minister, the Navy Minister, and the Chief of the Navy General Staff, direct access to the emperor.
In wartime, the Imperial Army General Staff formed part of the army section of the Imperial General Headquarters, an ad-hoc body under the supervision of the emperor created to assist in coordinating overall command.
Initially, under Ōmura Masujirō and his newly created Ministry of the Military Affairs (Hyōbu-shō), the Japanese military was patterned after that of Napoleonic France. However, the stunning victory of Prussia and the other members of the North German Confederation in the 1870-1871 Franco-Prussian War convinced the Meiji oligarchs of the superiority of the Prussian military model and in February 1872, Yamagata Aritomo and Oyama Iwao proposed that the Japanese military be remodeled along Prussian lines.
In December 1878, at the urging of Katsura Taro, who had formerly served as a military attaché to Prussia, the Meiji government fully adopted the Prussian/German general staff system (Großer Generalstab) which included the independence of the military from civilian organs of government, thus ensuring that the military would stay above political party maneuvering, and would be loyal directly to the emperor rather than to a Prime Minister who might attempt to usurp the emperor's authority.
The administrative and operational functions of the army were divided between two agencies. A reorganized Ministry of War served as the administrative, supply, and mobilization agency of the army, and an independent Army General Staff had responsibility for strategic planning and command functions. The Chief of the Army General Staff, with direct access to the emperor could operate independently of the civilian government. This complete independence of the military from civilian oversight was codified in the 1889 Meiji Constitution which designated that the Army and Navy were directly under the personal command of the emperor, and not under the civilian leadership or Cabinet.
Yamagata became the first chief of the Army General Staff in 1878. Thanks to Yamagata's influence, the Chief of the Army General Staff became far more powerful than the War Minister.
Furthermore, a 1900 imperial ordinance decreed that the two service ministers had to be chosen from among the generals (or admirals) or lieutenant generals (or vice admirals) on the active duty roster. By ordering the incumbent War Minister to resign or by ordering generals to refuse an appointment as War Minister, the Chief of the General Staff could effectively force the resignation of the cabinet or forestall the formation of a new one.
Of the seventeen officers who served as Chief of the Army General Staff between 1879 and 1945, three were princes of the imperial blood (Prince Arisugawa Taruhito, Prince Komatsu Akihito, and Prince Kan'in Kotohito) and thus enjoyed great prestige by virtue of their ties to the emperor.
The American Occupation authorities abolished the Imperial Army General Staff in September 1945.
Chief of the Army General Staff (general or Field Marshal)
Vice Chief of the Army General Staff (lieutenant general)
|1||24 Dec 1878 - 4 Sep 1882||Field Marshal Count Yamagata Aritomo|
|2||4 Sep 1882 - 13 Feb 1884||Field Marshal Oyama Iwao|
|3||13 Feb 1884 - 22 Dec 1885||Field Marshal Marquis Yamagata Aritomo|
|4||22 Dec 1885 - 14 May 1888||General Prince Arisugawa Taruhito|
|5||14 May 1888 - 9 Mar 1889||Lieutenant General Ozawa Takeo|
|6||9 Mar 1889 - 15 Jan 1895||General Prince Arisugawa Taruhito|
|7||26 Jan 1895 - 20 Jan 1898||Field Marshal Prince Komatsu Akihito|
|8||20 Jan 1898 - 11 May 1899||General Kawakami Soroku|
|9||16 May 1899 - 20 Jun 1904||Field Marshal Prince Ōyama Iwao [peer]|
|10||20 Jun 1904 - 20 Dec 1905||Field Marshal Prince Yamagata Aritomo [peer]|
|11||20 Dec 1905 - 11 Apr 1906||Field Marshal Prince Ōyama Iwao|
|12||11 Apr 1906 - 30 Jul 1906||General Kodama Gentarō|
|13||30 Jul 1906 - 20 Jan 1912||Field Marshal Baron Oku Yasukata|
|14||19 Jan 1912 - 17 Dec 1915||Field Marshal Hasegawa Yoshimichi|
|15||17 Dec 1915 - 17 Mar 1923||Field Marshal Uehara Yusaku|
|16||17 Mar 1923 - 2 Mar 1926||General Kawai Misao|
|17||2 Mar 1926 - 19 Feb 1930||General Suzuki Soroku|
|18||19 Feb 1930 - 23 Dec 1931||General Kanaya Hanzo|
|19||23 Dec 1931 - 3 Oct 1940||Field Marshal Prince Kan'in Kotohito|
|20||3 Oct 1940 - 21 Feb 1944||Field Marshal Sugiyama Hajime|
|21||21 Feb 1944 - 18 Jul 1944||General Tōjō Hideki|
|22||18 Jul 1944 - Sep 1945||General Umezu Yoshijiro|
|1||5 Dec 1878 - 16 Oct 1879||Field Marshal Ōyama Iwao|
|x||16 Oct 1879 - 6 Feb 1882||Post not filled|
|2||6 Feb 1882 - 21 May 1885||Lieutenant General Soga Sukenori|
|3||21 May 1885 - 16 Mar 1886||General Kawakami Soroku|
|4||16 Mar 1886 - 26 Jul 1886||Lieutenant General Soga Sukenori|
|5||26 Jul 1886 - 12 May 1888||Lieutenant General Ozawa Takeo|
|x||12 May 1888 - 9 Mar 1889||Post not filled|
|6||9 Mar 1889 - 20 Jan 1898||General Kawakami Soroku|
|x||20 Jan 1898 - 26 Aug 1898||Post not filled|
|7||26 Aug 1898 - 25 Apr 1900||General Osako Hisatoshi|
|8||25 Apr 1900 - 27 Mar 1902||Field Marshal Terauchi Masatake|
|9||17 Apr 1902 - 1 Oct 1903||Major General Tamura Iyozu|
|10||2 Oct 1903 - 12 Oct 1903||General Fukushima Sei|
|11||12 Oct 1903 - 11 Apr 1906||General Kodama Gentaro|
|12||16 Apr 1906 - 25 Apr 1912||General Fukushima Sei|
|13||25 Apr 1912 - 17 Apr 1914||Lieutenant General Oshima Ken'ichi|
|14||17 Apr 1914 - 4 Oct 1915||General Akashi Jiro|
|15||4 Oct 1915 - 10 Oct 1918||General Tanaka Giichi|
|16||10 Oct 1918 - 5 May 1921||General Fukuda Masataro|
|17||5 May 1921 - 24 Nov 1922||General Kikuchi Shinnosuke|
|18||24 Nov 1922 - 1 May 1925||Field Marshal Muto Nobuyoshi|
|19||1 May 1925 - 5 Mar 1927||General Kanaya Hanzo|
|20||5 Mar 1927 - 1 Aug 1929||General Minami Jiro|
|21||1 Aug 1929 - 22 Dec 1930||Lieutenant General Okamoto Renichiro|
|22||22 Dec 1930 - 9 Jan 1932||Lieutenant General Ninomiya Osamu|
|23||9 Jan 1932- 19 Jun 1933||Lieutenant General Masaki Jinzaburō|
|24||19 Jun 1933 - 1 Aug 1934||General Ueda Kenkichi|
|25||1 Aug 1934 - 23 Mar 1936||Lieutenant General Sugiyama Hajime|
|26||23 Mar 1936 - 1 Mar 1937||General Nishio Juzo|
|27||1 Mar 1937 - 14 Aug 1937||Lieutenant General Imai Kiyoshi|
|28||14 Aug 1937 - 10 Dec 1938||General Tada Hayao|
|29||10 Dec 1938 - 2 Oct 1939||Lieutenant General Nakajima Tetsuzo|
|30||2 Oct 1939 - 15 Nov 1940||Lieutenant General Sawada Shigeru|
|31||15 Nov 1940 - 6 Nov 1941||General Tsukada Osamau|
|32||6 Nov 1941 - 8 Apr 1943||Lieutenant General Tanabe Moritake|
|33||8 Apr 1943 - 21 Feb 1944||Lieutenant General Hata Hikosaburo|
|34||21 Feb 1944 - 7 Apr 1944||Lieutenant General Ushiroku Jun|
|35||7 Apr 1945 - Sep 1945||Lieutenant General Kawabe Torashiro|