After the death of Yoshisada, Yoshimori MOGAMI who was invited from a branch family of the Nakano clan became a puppet in the hands of the wife of Yoshisada from the Date clan who held the rein of power instead of him.
義定の死後は庶流中野氏から迎えた最上義守を傀儡として、伊達氏から迎えた義定の未亡人が権勢をふるった。