In December 1160, his father, Yoshitomo, banded together with FUJIWARA no Nobuyori and brought about a coup d'état in Kyoto and seized political power by killing his political foe FUJIWARA no Shinzei, then secured Retired Emperor Goshirakawa and Emperor Nijo in the Dairi (Inner Palace).
平治元年（1160年）12月、父の義朝は藤原信頼と結んで京都でクーデターを起こして政敵の藤原信西を殺し、後白河上皇と二条天皇を内裏に確保して政権を掌握した。