Abe no Seimei
He later taught Abe no Seimei the art of onmyōdō. Seimei became his successor in astrology and divination, while Yasunori's son succeeded him in the creation of the calendar, a lesser task. For several centuries afterward, the Abe clan controlled the government ministry of onmyōdō, while the Kamo clan became hereditary keepers of the calendar.