 During the Boshin War of the Meiji Restoration, he volunteered his services as an army medic accompanying the infantry supporting the Shogunate.After the Battle of Aizu in 1868, he made his way to Sendai, and enlisted with the Ōuetsu Reppan Dōmei.Briefly imprisoned after the war by the new Meiji government, he was released through the efforts of Yamagata Aritomo, who asked him to help develop the medical corps of the fledgling Imperial Japanese Army.