Ōuetsu Reppan Dōmei
Following the Battle of Sekigahara and the formal recognition of Morioka Domain under the Tokugawa shogunate, Kozukata Castle was renamed Morioka Castle. Its name was changed from to (both read as "Morioka") During the Boshin War of the Meiji Restoration, Morioka Domain was a key member of the pro-Tokugawa "Ōuetsu Reppan Dōmei."