Tokugawa Ietsuna
Tsunamura was the eldest son of Date Tsunamune by a concubine. His childhood name was Kamechiyo-maru (亀千代丸). He was later styled , but his name was changed to Date Tsunamura during his "genpuku" ceremony, which was held by "shōgun" Tokugawa Ietsuna. In later life, his courtesy title was "Sakonoe-gon-shōshō" (General of the Left Guards) and "Mutsu-no-kami" and his Court rank was Senior Fourth Rank, Lower Grade.