Nanbu clan
In July 1590, the 26th chieftain of the Nanbu clan, Nanbu Nobunao, made an oath of fealty to Toyotomi Hideyoshi at the Siege of Odawara, and was officially confirmed as "daimyō" of seven districts of northern Mutsu province (Nukanobu, Hei, Kazuno, Kuji, Iwate, Shiwa and Tōno). Hideyoshi assisted in the suppression of the Kunohe Rebellion of 1591 which secured Nobunao's position as head of all the branches of the Nanbu clan. However, Hideyoshi also recognised the independence of the Tsugaru clan, former Nanbu retainers, and their control over the three districts of Tsugaru Peninsula, but gave the Nanbu clan the additional districts of Hienuki and Waga as compensation. Nanbu Nobunao relocated his seat from Sannohe Castle to the more central location of Morioka, and began work on Morioka Castle and its surrounding castle town in 1592.