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.
Predecessors The
sankin-kōtai system was a natural outgrowth of pre-existing practices which were expanded by the Tokugawa shogunate to further their own political interests. Much of the reason the newly created shogunate could impose
sankin-kōtai on the defeated
daimyo with ease was due to these immediate predecessors.
Kamakura period The Tokugawa period philosopher
Kumazawa Banzan wrote in his
Daigaku wakumon that the
Kamakura shogunate had its own version of alternate attendance, which made
gokenin visit the shogun's court in
Kamakura for fifty days once every three years. Kumazawa claimed that his account was based on records preserved by the descendants of ancient Kamakura families. Modern scholars have been unable to confirm the existence of such detailed rules, but there is evidence that, at least in principle, Kamakura period
gokenin owed some kind of service at the shogun's court. The obligatory
ōyuka service required
gokenin to attend at the shogun's court for one month. They were also required to attend on special occasions such as comings of age, weddings, and funerals. The principal duty of the
gokenin was ''
, which was periodic guard duty at Kyoto and Kamakura. It originated as a public duty of the warrior class, requiring performance of guard service in Kyoto in one out of every three years. In 1186, Minamoto no Yoritomo made this service mandatory for gokenin
and reduced the duration to six months, and then later to three. In 1275, a similar arrangement was instituted at Kamakura, making gokenin
in eastern Japan serve there for one month annually. Important gokenin
who frequently performed guard service there maintained residences in Kamakura, even those from remoter regions in western Japan. It was also frequent practice for shugo and jitō'' to have their sons serve in the shogun's court, acting as hostages. In some cases, families were kept in Kamakura. These obligations on the Kamakura
gokenin had a limiting effect on local independence, like the more rigid
sankin-kōtai system that emerged in the Edo period. Shimmi Kichiji claimed that the prolonged absence of the
gokenin from their fiefs due to their obligatory attendance at the capital delayed the development of true feudalism in Japan. ==Description==