It is also stated that 'the raid took place when many samurai from Izu were away fighting for the Yamanouchi-Uesugi Clan in the Province of Kozuke, leaving Izu with a small number of samurai.
また、「討入りは、伊豆国の兵の多くが山内上杉氏に動員され上野国の合戦に出て手薄になったのを好機とした。