Sunpu Castle
was a Japanese samurai of the mid-Sengoku period. Longtime retainer of Matsudaira Hirotada and later, his son Tokugawa Ieyasu. When Ieyasu was sent to Sunpu Castle to be a hostage to the Imagawa clan, Tadayoshi served alongside Matsudaira Shigeyoshi as castle warden of Okazaki Castle. He was renowned as a model of frugality, eventually saving up enough money by the time Ieyasu returned, in order to rearm the Matsudaira (Tokugawa) clan. In later years, he was held up as the model Mikawa-era Tokugawa vassal.