Jinbō Norimune served as a bushō during the Sengoku period. Norimune was the head of the Jinbō clan as the deputy military governors of Etchū Province. Norimune was the son of Jinbō Naganobu. His own son was Jinbō Nagamoto. He had the title of Echizen-no-kami. In his youth, he had the name Noriyoshi and later changed to Norimune. In both cases, he received one of the characters in his name from his lord, Hatakeyama Hisanori (later known as Hisanobu), the military governor of Etchū. His younger brother, Jinbō Noriaki, also received one of the characters in his name from Hisanori.
Norimune was a retainer of Hatakeyama Masanaga (Hisanori’s father, the deputy shōgun of the Muromachi bakufu, and the military governor of Kawachi, Kii, Etchū, and Yamashiro provinces) and was the heir to Jinbō Naganobu who oversaw the period of peak prosperity for the Etchū-Jinbō clan. In 1498, Norimune went alongside his father, Naganobu, in support of a march upon Kyōto by Ashikaga Yoshiki (later known as Yoshitane), but, after this was blocked by the Rokkaku clan of southern Ōmi Province, he obeyed Yoshiki by staying under the protection of Ōuchi Yoshioki, a sengoku daimyō and head of the Ōuchi clan based in Yamaguchi in Suō Province.
Following the death of his father in 1501, Norimune overcame conflicts within the clan to become the next head of the Jinbō. However, in the third month of 1506, a sudden invasion by the Kaga Ikkō-ikki led to his defeat and forced a retreat. Norimune then turned to Nagao Yoshikage, the deputy military governor of Echigo, for support. Yoshikage responded in the eighth month by coming to support Norimune, whereupon the allied forces of the Nagao and Jinbō annihilated the ikki forces in a battle at the Rendai Temple in the Samue neighborhood of the Nei District of Etchū. Nevertheless, afterwards, the Jinbō forces failed to cooperate with the Nagao army. At the subsequent Battle of Hannyano, the Nagao forces were defeated by the ikki, while Yoshikage was killed in action. This event was viewed by Yoshikage’s son, Nagao Tamekage (the deputy military governor of Echigo), as an act of betrayal by Norimune, so, thereafter, the two families frequently clashed and turned into bitter rivals.
Norimune promoted an alliance through marriage with the Shimotsuma clan who served as the high priests of the Hongan Temple as well as reconciliation with the Ikkō-ikki religious band affiliated with the Hongan Temple. These actions were viewed as an effort to become independent of the Hatakeyama clan, the military governors of Etchū. In 1519, Hisanobu solicited support from Hatakeyama Yoshifusa of Noto (from the same family) and Nagao Tamekage, to raise an army under the command of Hatakeyama Katsuō to subjugate Norimune. Katsuō was the natural son of Hatakeyama Yoshihide and nephew treated as a son by Hisanobu.
While holed-up in Nijōzan Castle, Norimune endured a difficult battle, but repelled a sudden assault by the Noto-Hatakeyama forces to escape from a precarious situation. Yoshitane joined this conflict with Norimune and, in the eighth month of 1520, was defeated in battle against Tamekage who allied with Hisanobu at the Battle of Sakaigawa.
In the twelfth month of 1520, Norimune was subject to another attack by the allied forces of the Hatakeyama and Nagao at the Battle of Shinjō, and, after the defeat of the Jinbō and Shiina armies, killed himself while fleeing. Shiina Yoshitane also appears to have died in this conflict. Thereafter, Yoshitane’s son (Shiina Yasutane) competed against Norimune’s son (Jinbō Nagamoto) for influence in Etchū.
In 1519, Norimune recommended to the twenty-fourth generation head of the Shōjōkō Temple named Yugyō Shōnin Fugai to relocate to the harbor town of Hōjōzu in Etchū. Hōjōzu was the home town of this priest. At the time, the Shōjōkō Temple (the headquarters for the Jishū sect of Buddhism) was based in Fujisawa in Sagami Province. However, after Norimune took his own life toward the end of 1520, these plans were cancelled.