Mochinori's father Narinori took part in the movements of the northern domains which culminated in the creation of the Ōuetsu Reppan Dōmei during the Boshin War.

In his last act as lord, Mochinori distributed around 100,000 ryō of gold coins from the domain's treasury to the retainers.

However, under Mochinori's administration, a great many elementary schools were founded, along with a system by which the prefectural government funded students to study in Tokyo, and variety of other educational programs.

[1] He was replaced as governor of Okinawa in 1883, becoming a member of the Genrōin (Council of Elders in the central Tokyo-based government), and in 1884 he became a count (伯爵 hakushaku).

His tenure as governor of Okinawa was short, a result, it is said,[2] of Tokyo's disapproval of the extent of his reform programs in the prefecture at a time when there remained sovereignty disputes with China over the islands.