水戸藩
was a Japanese "daimyō" of the early Edo period, who ruled the Takamatsu Domain. Yorishige was the first son of Tokugawa Yorifusa, and Tokugawa Mitsukuni was the third son of Tokugawa Yorifusa, the first Tokugawa "daimyō" of Mito Domain; this made him the grandson of Tokugawa Ieyasu.