sankin-kōtai

thumb|350px| "En masse Attendance of Daimyo at Edo Castle on a Festive Day" from the Tokugawa Seiseiroku, [[National Museum of Japanese History]] Sankin-kōtai (, now commonly written as ) was a policy of the Tokugawa shogunate during most of the Edo period, created to control the daimyo, the feudal lords of Japan, politically, and to keep them from attempting to overthrow the regime. It required most daimyo to alternate between living in their domain and in the shogunate's capital, Edo, every year. This made the daimyo subject to constant surveillance from the shogunate. This also forced the daimyo to have residences in both their domain and Edo. The cost of maintaining several lavish residences as well as the journeys to and from Edo was a constant drain on the finances of the daimyo, which greatly increased the shogunate's control over them and kept them militarily weak. The daimyo were also required to keep their wife and children in Edo permanently to act as hostages.

==History== Toyotomi Hideyoshi had earlier established a similar practice of requiring his feudal lords to keep their wives and heirs at Osaka Castle or the nearby vicinity as hostages to ensure their loyalty. Following the Battle of Sekigahara and the establishment of the Tokugawa Shogunate, this practice was continued at the new capital of Edo as a matter of custom. It was made compulsory for the tozama daimyōs in 1635, and for the fudai daimyōs from 1642. Aside from an eight-year period under the rule of Tokugawa Yoshimune, the law remained in force until 1862.