Shiina Yoshitane served as a bushō during the Sengoku period.
The Shiina were a kokujin, or provincial family of influence, and Yoshitane was the deputy military governor of the Niikawa District in Etchū Province. He was commonly known as Shinshichirō. Yoshitane received one of the characters in his name from Hatakeyama Hisanobu, the military governor of Etchū. Yoshitane may have been the son of Shiina Nobutane (Shirōjirō).
Jinbō Noriimune was the head of the Jinbō clan serving as the deputy military governors of Etchū. 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 (the deputy military governor of Echigo), 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 Jinbō 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. 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.