Ashikaga Yoshimasa
In 1464, a succession dispute erupted over the shogunate itself. The shōgun, Ashikaga Yoshimasa, was considering retirement. Hosokawa supported the Shōgun's brother, Ashikaga Yoshimi as the successor. Hino Tomiko, who was the mother of Ashikaga Yoshihisa, was against her husband's decision to give the shogunate to Yoshimi, so she sought military support to secure the succession of her son Yoshihisa. Yamana chose to support Yoshihisa, the Shōgun's infant son.