Born in Tokuyama, Yamaguchi as the 10th son of the lord of a branch of the Tokuyama Clan, Hiroshige Mori, and adopted by the lord of the main Hagi Clan, Takachika Mori. During his time as the designated heir, he supported the sonno joi undo (movement to revere the emperor and expel the barbarians), and busily engaged in affairs of state. In connection with the Kinmon Incident in 1864, he was stripped of his official rank. In 1867, when the coup d'etat of osei fukko (restoration of Imperial rule) was realized, he regained the rank, and became gijo (one of the three highest posts in the beginning of the Meiji government), sangi (councillor), and so on. After succeeding the lord of the Yamaguchi Clan, he became governor of the Yamaguchi Clan according to hanseki hokan (the return of the lands and people to the Emperor) in 1869. After haihan chiken (the abolition of clans and establishment of prefectures), he resigned as governor, and successively assumed the offices of president of Dai Jugo Kokuritsu Ginko(the 15th National Bank) and its director. In 1890, he became a member of the House of Peers, and in 1884 became koshaku (prince). He was accorded a state funeral.