He was the 18th son of Nariaki TOKUGAWA, the ninth lord of domain and younger paternal half-brother of Yoshinobu TOKUGAWA, the 15th seii taishogun (literally, "great general who subdues the barbarians").
第9代藩主徳川斉昭の18男、第15代征夷大将軍徳川慶喜の異母弟にあたる。