Since then, he waged battles against the Koga Kubo (the Ashikaga family based in Koga, the Kanto region) led by Nariuji for nearly 30 years, but failed to control throughout the Kanto region because he was not given sufficient military forces by the bakufu which was engaged in the Onin war in those days.
以後、成氏の古河公方勢力と30余年に渡る抗争を繰り広げたが、当時幕府は応仁の乱の最中であったため満足な軍事力を付与してもらうことができず、関東一円を制することは叶わなかった。