Yoshitoyo was the eldest son of Satomi Yoshimichi and may have hoped to become the new lord once he came of age. In 1533 he rebelled against his uncle Sanetaka and forced him to commit suicide. The following year, Satomi Yoshitaka gathered an army and attacked Yoshitoyo at Inamura castle. Faced with overwhelming odds, Yoshitoyo committed suicide in May 1534.
- Initial text from Sengoku Biographical Dictionary (Samurai-Archives.com) FWSeal & CEWest, 2005