Lifespan: Kōji 1 (1555) to 8/10 of Genki 2 (1571)
Clan: Mōri → Izuha
Lord: Mōri Motonari → Mōri Terumoto
Father: Mōri Motonari
Mother: Miyoshi clan
Adoptive Father: Izuha Motosuke
Siblings: Mōri Takamoto, Kikkawa Motoharu, Kobayakawa Takakage, Ninomiya Naritoki (?), Hoida Motokiyo, Mōri Motoaki, Mototomo, Amano Motomasa, Suetsugu Motoyasu, Mōri Hidekane, other
Izuha Mototomo served as a bushō during the Sengoku period. He had the common name of Magoshirō.
In 1555, Mototomo was born as the sixth son of Mōri Motonari. He was adopted by Izuha Motosuke, a kokujjin, or provincial landowner, based in Izuha in the Ōchi District of Iwami Province. Motosuke was the lord of Izuha-Futatsuyama Castle. Mototomo adopted the Izuha surname, but, in 1571, died at the age of seventeen. After the death of Mototomo, Motosuke’s natural son, Izuha Motokatsu, became his successor.
Mototomo died just two months after the death of his natural father, Motonari. To avoid misunderstandings, Motosuke sent a written oath to Motonari’s successor, Mōri Terumoto, reaffirming his loyalty to the Mōri clan. Later, Buddhist memorial services marking the 150th and 200th anniversaries of Mototomo’s death were held at the Tokutonari Temple (affiliated with the Nanzen Temple branch of the Rinzai sect) in Fukugenzen in Hagi in Nagato Province.