The Honnôji triple kô game

Go world 6, March-April 1978
Page from go history
White : Nikkai (1st Honinbo Sansa)
Black : Kashio Rigen
No komi
Played at the Honnôji Temple in Kyôtô on the 1st June 1582, in the presence of Oda Nobunaga.

Nikkai (1559-1623), a Buddhist priest, was the strongest player of his day and founded the Honinbô House of Go players. He is better known as the 1st Honinbô Sansa. Kashio Rigen was his leading rival and one of his disciples founded the Hayashi House.
The circumstances of this game make it one of the most famous in Go history. It was played in the presence of Oda Nobunaga (1534-1582), the first of three great military overlords who carried out the unification of Japan after a century of civil war. Nobunaga was a keen player and took a 5-stone handicap from Sansa in teaching games.

A triple kô is supposed to have arisen in this game, leading to its suspension without a result. The night after the game, Nobunaga’s ally Akechi Mitsuhide (1526-82) suddenly rose in rebellion, surrounded the Honnôji Temple with his troops and killed Nobunaga. Because of this, a triple kô was thereafter regarded as inauspicious.

Sansa fortunately found patrons in Nobunaga’s successors, Toyotomi Hideyoshi who promptly disposed of Akechi, and Tokugawa Ieyasu (1542-1616), who founded the Tokugawa shogunate which ruled Japan for two and a half centuries. Sansa was appointed to the office of Godokoro and played a crucial role in opening up the golden age of Japanese Go.

The moves after 128 are not recorded, nor is the result, but the game seems won by white and it is hard to imagine a triple kô could come up. There is a theory that it actually occurred in another game played on the same day. There is a detailed analysis of another Sansa-Kashio Rigen game in Go Review, Autumn 1973.