Shōkai
Shōkai was a Buddhist monk of the Ji-shū school, disciple and close relative of Ippen, the first patriarch of Ji shū. He was also considered the founder of the Rokujō-ha branch of the school.
After Ippen's death in 1289, he founded the Kankikō-ji temple in 1291, and most importantly wrote the text of the Illustrated Biography of the Itinerant Monk Ippen. This is the oldest biography of the patriarch known today, so it has a very strong historiographical value.