 He decided to move his seat south from its former location at Sannohe Castle and to erect a new castle at Morioka.The design of the new castle may have been influenced by Nagoya Castle in Hizen Province, which he saw during the Japanese invasions of Korea.His holdings were re-confirmed after the Battle of Sekigahara by Tokugawa Ieyasu, and Morioka remained the seat of the Nanbu clan until the Meiji Restoration.