Nikkai was born in Kyōto and became a monk at age nine. The name "Hon'inbō",, comes from a sub-temple of the Jakkōji temple complex in Kyōto where Nikkai, the first "Hon'inbō", resided. Among his students were the daimyōsOda Nobunaga, Toyotomi Hideyoshi, and Tokugawa Ieyasu, the three great "unifiers" of feudal Japan. Nikkai considered the three generals to be "fifth-degree" players, but "diplomacy" was likely a factor in Nikkai's even-handed assessment of these imposing figures. It was Nobunaga who, in 1578, recognized twenty-year-old Nikkai as the first Meijin of Go. In 1582, Nikkai, at the behest of Nobunaga, was involved in a notorious game at the Honnōji Temple against his rival, another Nichiren priest, Kashio Rigen. The game is traditionally held to have taken place on the eve of the treacherous Incident at Honnōji,, and is said to have ended in a "triple ko". Hence the notion of triple ko as bad omen. There is a game record, but typical for the period, it is incomplete. The triple ko may have occurred, somewhat implausibly, in unrecorded remaining plays, or in another game that day, but in the end, there is no evidence that this is more than a good story. In 1587, Nobunaga's successor, the regent Hideyoshi gave Nikkai an official position,, granting his temple an annual four koku of rice and setting up a tournament that he attended in person. In 1592, Nikkai was given the rank of Gon-no-Daisoku by the Go-Yōzei Emperor. In 1603, the Go-Yōzei Emperor recognized sixty-year-old Tokugawa Ieyasu as shōgun, inaugurating the 250-year rule of the Tokugawa bakufu. At the direction of Ieyasu, Nikkai turned priestly duties at Jakkoji over to his younger brotherNichiei and became the first go-dokoro, in which office Nikkai was provided fifty koku of rice and five servants. Also around this time, Nikkai took the name Hon'inbō Sansa. Sansa was also a strong shogi player, but in the Tokugawa period, go was organised into four "houses", and shogi into three, which would compete in oshirogo "Castle Go" tournaments for the title Meijin. The official nature of these arrangements meant that go and shogi masters held different offices. In 1612, eight go and shogi players were given individual state support. This system persisted over two and a half centuries, until the collapse of the Tokugawa government itself in the Meiji Restoration. The beginning of the oshirogo matches in Edo, seat of the Tokugawa government, meant that at the end of each year, Sansa had to travel east for a month. He is said to have turned down an official residence in Edo's early Nihonbashi district, but was given other accommodations. Sansa died in Edo at the age of 65.
Legacy
Honinbō Sansa was succeeded by a youth named Sugimura, who due to his age, had to wait several years after Sansa's death to re-establish the Hon'inbō house as Hon'inbō San'etsu when he turned twenty. However, the title of Meijin was regained by the third head of Hon'inbō, and altogether, seven of the ten generations of historic Meijin were Hon'inbō. In addition, all three traditional Kisei were Hon'inbō masters. The school established by Hon'inbō Sansa, along with the Inoue and Yasui schools, lasted into the 20th century, but struggled without government backing. In 1936, the last Hon'inbō master, the controversial Hon'inbō Shūsai, turned selection of the Hon'inbō title over to the Nihon Ki-in.
