He was born in a village in Akō District, Harima, the son of the doctor Kobayashi Naosuke, and named Keitarō. He entered the Okayama domain's Shizutani School, where his father had also studied, and spent five years learning Chinese classics, Confucianism and Chinese medicine. The boy raised in a doctor's home would later broaden his interests to military science and engineering.
After assisting a Western-style doctor at home and changing his name to Keisuke, he went to Osaka and entered Ogata Kōan's Tekijuku, studying Dutch and Western medicine. The Tekijuku was a place where young men from all over the country studied in competition, and the Dutch he mastered there became the foundation for reading Western books on military science and technology.
He went to Edo with friends from the Tekijuku and, while helping with translation work, became head student of the Tsuboi school. From this time his interest shifted from medicine to Western military science, engineering and photography. He also came to know Katsu Kaishū and grew determined to use new knowledge to help defend the country.
Invited to teach military science at the Egawa school, he also studied English with Nakahama Manjirō, who had lived in America after being shipwrecked. The next year he was taken into the Amagasaki domain, which ruled his home village, as a retainer. Adding English to Dutch greatly widened the knowledge open to him.
Consulting Dutch technical books, he taught craftsmen how to make movable metal type, producing the first alloy type in Japan. Called the Ōtori type, it was used to publish one translation after another, such as books on Western artillery. His book on fortification was well received and reportedly used as a reference for actual castle building in Chōshū. He also experimented with photography, thermometers and balloons.
Made a shogunate retainer, he joined in forming the shogunate's Denshūtai, trained in the French military system, and became an infantry commander. The next year he was promoted to infantry commissioner, among the highest posts in the shogunate army. In councils after the Battle of Toba–Fushimi, he strongly urged continuing the war with Oguri Tadamasa and Enomoto Takeaki.
On the day Edo Castle was surrendered, he slipped out of Edo with the Denshūtai and fought the new government's forces at Utsunomiya, Aizu and elsewhere. He joined Hijikata Toshizō and others, but after heavy losses in a mountain-pass battle he fell back to Sendai. There he joined Enomoto Takeaki's fleet and crossed to Ezo for the last battles of the Boshin War.
He became head of the army in the Hakodate regime and fought doggedly with delaying tactics in the Battle of Hakodate, but was gradually cornered and surrendered at Goryōkaku. Sent to Tokyo and imprisoned, he kept a diary of his transport. As a commander on the losing side, he spent days with no future in sight.
Pardoned through the efforts of Kuroda Kiyotaka and others, he left prison and was invited into the new government for his knowledge. Serving in the Colonization Office developing Hokkaidō, he toured Western countries to negotiate public loans and inspect machinery. In the government of his former enemies, he devoted himself as a technical expert to building a new Japan.
At the Ministry of Public Works he oversaw state factories and advanced enterprises in cement, glass, shipbuilding and spinning. That year he became the first head of the Imperial College of Engineering, forerunner of the University of Tokyo's engineering faculty, and trained many engineers. He also launched Japan's first industrial magazine to spread knowledge of new technology.
After serving in the Genrōin, he became head of the Peers' School and also principal of the Peeresses' School. Beyond his experience as an engineer, he took on heavy duties in education. His path from shogunate army commander to a pillar of Meiji school education reflects the great changes of the age.
Turning to diplomacy, he became minister to Qing China and later also to Korea. Just before the First Sino-Japanese War he went to Korea and handled difficult negotiations with Yuan Shikai of Qing and others. After war broke out he was relieved as minister, returned home and became a privy councillor advising the emperor.
He was made a baron for his long service, but in his later years he suffered misfortunes, such as being struck by a disaster and losing sons before him. He died of illness at his villa in Kōzu, Kanagawa. Skilled in Chinese verse and waka, he left records of the Boshin War and introduced Western evolutionary theory, a man who lived by wide-ranging knowledge.
Ogata KōanKatsu KaishūOguri TadamasaHijikata ToshizōEnomoto TakeakiKuroda KiyotakaTanabe Sakurō
Kawanabe KyōsaiNakamura MasanaoTerashima MunenoriKido TakayoshiEtō ShinpeiFukuzawa YukichiIwasaki YatarōMaejima Hisoka
People of the Meiji period ・ People by period
Based on facts found in textbooks and biographies. Uncertain points are marked as such.