He gained the trust of Emperor Goshirakawa during the Hogen Disturbance and then prevailed in the Heiji Disturbance, and as a result, he became the first warlord to be appointed Dajo-daijin (Chancellor of the Realm).
保元の乱で後白河天皇の信頼を得て、平治の乱で最終的な勝利者となり、武士では初めて太政大臣に任ぜられる。