Norimune fought in the Onin War on the side of the Eastern army to recapture the former fief of the Akamatsu clan from Sozen YAMANA, and as a result, the Akamatsu clan recaptured the fief and were appointed to shugo of Harima, Bizen and Mimasaka Provinces.
応仁の乱では山名宗全から領国を奪回するために東軍に属して戦い、赤松氏が旧領国を回復し播磨、備前、美作の守護に任じられたのは則宗の力によるところが大きい。