安倍晴明
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.