He and his brother and the minister SOGA no Umako supported the administration of Empress Suiko and Shotoku Taishi (Prince Shotoku), and built up a strong connection with Jogu Oke (the highest royal family) led by Shotoku Taishi.
大臣である兄・蘇我馬子とともに推古天皇・聖徳太子の執政を支えるが、その過程で聖徳太子一族（上宮王家）との結びつきを深めた。