Gosankyo

The Gosankyō (御三卿^?, "the Three Lords") were three branches of the Tokugawa clan of Japan. They were descended from the eighth of the fifteen Tokugawa shoguns, Yoshimune (1684–1751). Yoshimune established the Gosankyo to augment (or perhaps to replace) the Gosanke, the heads of the powerful han (fiefs) of Owari, Kishū, and Mito. Two of his sons, together with the second son of his successor Ieshige, established the Tayasu, Hitotsubashi, and Shimizu branches of the Tokugawa. Unlike the Gosanke, they did not rule a han. Still, they remained prominent until the end of Tokugawa rule, and some later shoguns were chosen from the Hitotsubashi line.

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