When he could no longer tolerate the oppressive measures being forced upon him by Takanobu RYUZOJI, Harunobu ARIMA asked Yoshihiro and Ieshisa, who were garrisoned in Yatsushiro, to send reinforcements.
龍造寺隆信の圧迫に耐えかねた有馬晴信が八代にいた義弘・家久に援軍を要請してきた。