He went to Edo in 1856 and studied Confucianism and military science.
Later he became associated with the group in Yosa that favored restoration of power to the emperor. In 1866 he was ordered by his domain to make an inspection tour of Nagasaki and Shanghai. In 1868, after his return to Japan, he served as a commander in the Boshin civil war, which took place between the imperial forces and those that remained loyal to the shogunate, fighting in a number of engagements. In 1869 he served in the central government, but later returned to Tosa and devoted himself to reforms in the administration of the domain.
In 1871 he resumed service in the central government, holding the post of chief assistant in the Ministry of Military Affairs. Later he served as head of the military court, commander of the Kumamoto Garrison, and in other posts. In 1874 he was active in suppressing the rebellion in Saga and dispatching troops to Taiwan. In 1876 he once more became commander of the Kumamoto Garrison, and in the Seinan War of 1877 won fame for his brilliant defense of Kumamoto Castle against the attacks of the rebels. In 1878, he advanced to the rank of lieutenant general and, as Eastern Army Supervisor, he took his place among the military leaders of the nation. He later held the posts of head of the Military Academy and Army Supervisor.
Because of disagreement with Yamagata Aritomo, the outstanding army leader of the time, he resigned from service. In 1885 he became minister of agriculture and commerce in the first Ito cabinet, but because of his opposition to Westernization and to Foreign Minister Inoue’s handling of treaty revision, he resigned in 1887. Thereafter he became an exponent of nationalism, forming a new conservative party and in 1890 becoming a member of the Upper House of the Diet. He also served as head of the Peers’ School and of the Peeresses’ School.
After his resignation he entered political life and in 1881 formed a political party known as the Chuseito to oppose the popular rights movement of the time.
Because of his conservative principles, he opposed clan factionalism in the government and the Russo- Japanese War and advocated measures to aid and protect the lot of the farmers.