daimyo

Daimyō were powerful Japanese feudal lords who ruled large domains and maintained private samurai armies during the late medieval and early modern periods. The term, meaning “great name” or “great lord,” designated leaders who controlled substantial landholdings and wielded independent military and political authority within their provinces, albeit under the overall authority of a shogun or the imperial court.

Daimyō governed territories called han and based their power on the productivity of the land, measured in koku, the amount of rice needed to feed one person for a year. Most daimyō controlled han valued at a minimum of 10,000 koku, a threshold that established them as distinct from lesser lords. During the Sengoku period (c. 1467–1603), daimyō were the principal warlords who vied for territory and influence, with some eventually aligning with or being absorbed by stronger states such as those led by Oda Nobunaga, Toyotomi Hideyoshi, and Tokugawa Ieyasu.

In the Edo period (1603–1868), the Tokugawa shogunate formalized and stabilized daimyō power through mechanisms designed to prevent rebellion and unify control. The system required the daimyō to maintain alternate residences in Edo (the sankin-kotai or attendance in Edo) and to oversee their domains while contributing to centralized governance. The shogunate exercised influence over succession, marriage alliances, and revenue, maintaining a balance among rival lords.

Following the Meiji Restoration, the han system was abolished in 1871, and domain boundaries were reorganized into prefectures. The former daimyō class was incorporated into the kazoku, a new peerage that reflected loyalty to the modern state while preserving hereditary status.