In Shikoku, Motochika CHOSOKABE of Tosa Province made relation by marriage with a vassal of the Akechi family, Toshimitsu SAITO, and had been making effort to unify Shikoku under amicable relation with Nobunaga through Mitsuhide.
四国では、土佐国の長宗我部元親が明智家臣斎藤利三と姻戚関係を結び、光秀を通じた信長との友好関係の下で統一を進めていた。