Buzen Nichigen (豊前日源, before 1263 – 1315) was a disciple of Nichiren who converted along with the rest of the Tendai temple Jisso-ji (實相寺) to Nichiren Buddhism in 1270.^[1] Nichiren's letter Jissoji gosho (實相寺御書, 1278) is addressed to him.^[2] Later, he joined Nichiren on Mount Minobu, and founded several temples after Nichiren's death.