one of the heroes of the Meiji Restoration, the overthrow of the 264-year rule by the Tokugawa family and return of power to the Japanese emperor. After the imperial restoration of 1868, Kido became one of the most effective officials in the new government.

Born into an influential warrior family, Kido early became active in the politics of his han, or fief, of Chōshū. As a student of Yoshida Shōin, he was close to the group of Chōshū leaders who were to lead the movement for the overthrow of the Tokugawa. The radical elements in Kido's han began to rise in power, and, in 1862, Kido became one of Chōshū's leading officials.

Alarmed by the growing power of the radicals there, the Tokugawa led a punitive expedition against Chōshū in 1865. Kido was ousted from his position, and a conservative government was installed. But the radicals had formed their own military forces, and, after the Tokugawa army withdrew, they again seized command and successfully repulsed a second Tokugawa expedition. As head of the Chōshū government, Kido began to negotiate with radical samurai from Satsuma. Kido, along with Ōkubo Toshimichi and Saigō Takamori of Satsuma, became known as one of the three giants of the Restoration. Together they headed the coup d'état that eventually toppled the shogun and restored the emperor to power.

Kido became one of the most powerful men in the new administration. He was one of those responsible for transferring the imperial capital from Kyōto to Edo (renamed Tokyo) and for persuading the heads of the large han to renounce possession of their domains, which were returned to the emperor. The small han then followed suit, and Kido helped devise a scheme to redivide the country into prefectures to be governed by officials appointed by the central administration.

Kido, who had accompanied other high government figures on a visit to Europe in 1871, returned in time to block a plan to invade Korea. He retired from the administration when his views opposing an expedition against Taiwan in 1874 were overruled. After the recall of Japan's forces, he returned to office and began to work for the establishment of a Western-style constitution, but ill health forced him to assume a less-active role in government.