A warrior of Harima Province, his real name was Akamatsu Norimura, widely known by his Buddhist name Enshin. In 1333, he answered Emperor Go-Daigo's call to overthrow the shogunate, fighting shogunate forces from his base at Kokenawa Castle in Harima. He skillfully deflected attacks from the Rokuhara Tandai while supporting Ashikaga Takauji's assault on Kyoto. Under the Kenmu Restoration, he expected to be appointed shugo of Harima but was insufficiently rewarded and grew discontented. He later sided with Takauji against the Southern Court, laying the foundation for the Akamatsu clan's rise as powerful shugo daimyo of Harima.

A provincial warrior with the boldness to rise in arms and the tactical eye to read the battlefield. His strong-willed nature showed in his willingness to act on grievances over inadequate rewards.

The Akamatsu clan flourished as shugo daimyo of Harima, Bizen, and Mimasaka in the Muromachi period. Akamatsu Mitsusuke, who assassinated Shogun Yoshinori in the Kakitsu Incident (1441), was Enshin's descendant.