Nanbu clan
In 1821, the Sōma Daisaku incident, in which a retainer of the Nanbu clan attempted to assassinate the "daimyō" of Tsugaru Domain occurred. The Nanbu clan and the Tsugaru clan had been enemies for centuries. This was the same year during which the domain faced its most serious crisis. The 11th "daimyō", Nanbu Toshimochi, died at the age of 13 before he could be formally received in audience by "shōgun" Tokugawa Ienari. Fearing that this could be used by the shogunate as a cause for attainder, the domain leaders substituted a cousin of similar age and appearance to take his place.