Born to a low-ranking Choshu samurai family, he studied under Yoshida Shoin at the Shoka Sonjuku and absorbed loyalist ideology. He joined the Kiheitai militia created by Takasugi Shinsaku and distinguished himself in the Shimonoseki War and the Boshin War. After the Meiji Restoration he traveled to Germany and France to study modern military systems and on his return worked to establish the Conscription Ordinance of 1873 and a modern military structure. He was deeply involved in drafting the Imperial Rescript to Soldiers of 1882, forming the spiritual foundation of the Imperial Japanese Army. In politics he served twice as Prime Minister (first cabinet 1889-91, second 1898-1900) and advanced the organization of the Interior Ministry and military bureaucracy. As a symbol of clique politics, he defined the power structure of the Meiji government, sometimes cooperating with and sometimes opposing Ito Hirobumi. Even in old age he influenced Taisho politics as a behind-the-scenes power broker. He died at eighty-three on February 1, 1922. He also had a passion for garden design, leaving celebrated gardens at his villas in Tokyo, Odawara, and Kyoto.