Four go houses

In the history of go in Japan, the four go houses were four major schools of go instituted, supported, and controlled by the state, at the beginning of the Tokugawa shogunate. (There were also many minor houses.) At roughly the same time shogi was organised into three houses. Here "house" implies institution run on the recognised lines of the iemoto system common in all Japanese traditional arts. In particular the house head had, in three of the four cases, a name handed down: Inoue Inseki, Yasui Senkaku, Hayashi Monnyu. References to these names therefore mean to the contemporary head of house.

The four houses were the Honinbo, Hayashi, Inoue and Yasui. They were originally designed to be on a par with each other, and competed in the official castle games called oshirogo.

The first of the four houses was the house Honinbo, founded by Honinbo Sansa. Honinbo Sansa was a Buddhist monk, and had been appointed Godokoro (minister of Go) by Tokugawa Ieyasu after the unification of Japan in 1603.

They were also nominally Buddhist institutions, with the Honinbo and Hayashi aligned with the Nichiren sect, and the Inoue and Yasui with the Jodo Shu. All players were therefore male. Some outward forms only persisted of that connection, with the oshirogo games being played in Buddhist dress and with shaven heads; the stylish Ota Yuzo was given a waiver of the obligation since he was proud of his hair. After Honinbo Doetsu made a representation that long sleeves were troublesome for the players, a dispensation for shorter sleeves was allowed to them. At least in theory, matters on succession in the houses was subject to the authority of the jisha bugyo, an official regulating religious establishments. Nominations as heir, typically within the iemoto system of the best disciple, who might not be a natural son but in effect adopted, were supposed to be made official. Deaths at an early age particularly affected the Honinbo house, and irregular succession could occur with potential for scandal.

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