When the eleventh Shogun Yoshitane ASHIKAGA was expelled from the shogunate by his cousin Yoshizumi ASHIKAGA and escaped safely to Saigoku (western part of Japan), Nobutaka appointed not only a trusted vassal Nobutaka UENO who had come with Yoshitane to the lord of Kimurayama-jo Castle in Bicchu Province, but also Masayuki NIKAIDO and Sadanobu ISE to the lords of the other castles at the neighboring spots to make them form the power of the Yoshitane side in Saigoku.
信孝は11代将軍足利義稙が従弟　足利義澄に将軍職を追われて、西国に落ち延びると、動向した近臣　上野信孝をして備中国鬼邑山城に封じたのをはじめ、二階堂政行、伊勢貞信もその近隣の諸城に封じて西国における義稙方勢力の形成にあたらせた。