Taking advantage of the Kyotoku War (series of battles between the Muromachi bakufu (Japanese feudal government headed by a shogun) and the Kanto kanrei (shogun's deputy for the Kanto area), he attacked and destroyed the head family of the Chiba clan, and became the 19th head of the clan.
享徳の乱に乗じて、千葉氏宗家を攻め滅ばしてその19代当主となる。