Born in Edo as the second son of shogunate retainer Enomoto Takenori, he studied navigation and gunnery at the Nagasaki Naval Training Center and from 1862 studied naval technology and international law in the Netherlands. After returning home he became a central figure in the shogunate navy. When the Boshin War broke out he commanded the shogunate fleet, broke out of Edo, and formed the Enomoto Fleet. Establishing his base at Hakodate and Goryokaku, he founded the Republic of Ezo (1868) and was elected president by Japan's first Western-style election by ballot. He was defeated by Meiji forces in the Battle of Hakodate in 1869 and surrendered. He was imprisoned but later pardoned thanks to appeals from Satsuma samurai including Kuroda Kiyotaka. Recruited by the Meiji government he demonstrated his ability, concluding the Treaty of Saint Petersburg with Russia (1875) as minister to Russia. He subsequently held key posts including Navy Minister, Minister of Communications, Education Minister, Foreign Minister, and Minister of Agriculture and Commerce. He died at seventy-two on October 26, 1908.