Shibukawa Shunkai (渋川 春海)(December 27, 1639 – November 1, 1715)
Japanese scholar, go player and court astronomer. Son of Yasui Santetsu, calling himself initially (after his father) Yasui Santetsu II. He later changed his name to Shibukawa Shunkai. Main character in Tow Ubukata's novel (adapted to film in 2012) Tenchi Meisatsu (天地明察), he had a fondness for Tengen play.