Ōuetsu Reppan Dōmei
In 1868, during the Boshin War of the Meiji restoration, the castle was the site of the Battle of Shinjō. Following the defection of Kubota Domain from the Ōuetsu Reppan Dōmei, Shinjō Domain soon followed suit. Shinjō Domain was then invaded by the armies of neighboring Shōnai Domain, and in the subsequent battle, Shinjō Castle and much of its surrounding castle town was destroyed.