The Tosa domain was a feudal domain whose leaders joined the movement that overthrew Japan’s Tokugawa shogunate. Its alliance with Satsuma and Chōshū helped bring about the Meiji Restoration, a decisive rupture with a political order that had restricted trade and concentrated authority in the shogun.

Place in Tokugawa Japan

In the nineteenth century, Japan was governed by the Tokugawa shoguns, while the emperor had been reduced to a ceremonial role. Feudal lords ruled and taxed their own domains, and society was organized through strict occupational categories, trade restrictions, and heavy taxation on farmers. The shogun controlled foreign trade from Edo and barred foreigners from the country.

The shogun’s authority was not absolute in practice. The Satsuma domain retained substantial autonomy and traded independently through the Ryūkyū Islands. Tosa was another domain whose leaders entered the political opposition to the shogunate as debate over Japan’s future intensified.

Alliance and Overthrow

In autumn 1867, Ōkubo Toshimichi of Satsuma traveled to meet Chōshū leaders. He proposed that they combine their forces, march on Edo, and overthrow the shogun. Leaders of Tosa and Aki had already joined the undertaking; Chōshū’s agreement completed the secret Satcho Alliance.

The Tosa connection also appears in the reform proposals associated with Sakamoto Ryūma, a signer on the Tosa side of an agreement with Satsuma. The agreement invoked the need for a single ruler, but the political aim went beyond restoring the emperor’s position. Sakamoto later presented the shogun with an eight-point plan urging him to resign and avert civil war. Its first clause called for political power to return to the Imperial Court; other provisions proposed two legislative houses and government measures based on general opinion.

Role in the Meiji Transformation

The Tosa leaders’ participation connected the military coalition against the shogun to a wider institutional program. The lords of Satsuma, Chōshū, Tosa, and Aki overthrew the shogun and established the Meiji Restoration. The change opened a path toward institutional reform and economic growth, away from the restrictive feudal order described in the account.

Tosa’s significance therefore lies not simply in its place among Japan’s domains, but in its role within a coalition whose challenge to shogunal rule altered the country’s political direction. The evidence identifies Tosa as a participant in that alliance and reforming movement; it does not detail the domain’s subsequent fate as a separate political unit.