Ujinori Uesugi was appointed Shitsuii (steward) when Mochiuji Ashikaga became governor-general of Kanto District ( 1409). Shortly after he fell out with Mochiuji when the latter confiscated the feudal fief of a relative of his and he resigned (1411).
Later he joined forces with Mitsutaka, the younger brother of Mitsukane, and attacked his former employer and forced him out of Kamakura and installed Mitsunaka as governor-general of Kanto (1416). Hearing of this Shogun Yoshimochi Ashikaga sent an army from northeast Japan to support the deposed Mochiuji. When the Shogun's army marched into Kamakura many followers of the rebels joined them and Mitsutaka, Mochinaka and Ujinori committed suicide rather than face defeat (1416).