Soga clan
After the regency of Shōtoku Tenchi ended the Soga clan, from which Shōtoku's ancestry was derived, took hegemony of the Yamato court. The clan was opposed to Shōtoku's son Yamashiro Ōe and killed him in 643. Under the reign of Empress Kōgyoku the Soga clan head, Soga no Iruka, was virtually an almighty leader of the court.