While Sozen, having contributed to the pacification of Kakitsu Incident, was against the reinstatement of the Akamatsu family who had masterminded the incident, he and his son-in-law Katsumoto came to an outright confrontation as Katsumoto appointed Masanori AKAMATSU shugo of Kaga Province in 1458 with a view to weakening Sozen's influence.
嘉吉の乱鎮圧に功労のあった宗全は主謀者赤松氏の再興に反対していたが、1458年、娘婿の勝元が宗全の勢力削減を図って赤松政則を加賀国守護職に取立てたことから両者は激しく対立するようになっていた。