Toyomoto was the son of the first Môri Hiromoto. From 1461-1462, he defeated Hatakeyama Yoshinari's army in Kawachi and Kii. In 1465, he dispatched troops to help Kobayakawa Hirohira when Oûchi Masahiro invaded his holdings. During the fall of the same year, Oûchi made a move to intervene in the war between the Hosokawa and Kawano clans. Toyomoto took action at the request of the Hosokawa, and blocked the Oûchi. In 1471, taking advantage of the confusion generated by the Ônin War, Toyomoto shifted his allegiance to the Ôuchi and came to serve Ôuchi Masahiro.
- Initial text from Sengoku Biographical Dictionary (Samurai-Archives.com) FWSeal & CEWest, 2005