Lifespan: Kanshō 5 (1464) to 9/19 of Eishō 3 (1506)
Rank: sengoku daimyō
Title: Governor of Shinano
Lord: Uesugi Fusasada → Uesugi Fusayoshi
Father: Nagao Shigekage
Siblings: Yoshikage, sister (formal wife of Yamayoshi Yoshimori) (?)
Wives: [Formal] Hōjū-in; [Consort] Daughter of the Shinano-Takanashi clan
Children: Daughter (wife of Iinuma Masakiyo), Tamekage, daughter (second wife of Uesugi Sadazane), daughter (wife of Sanponji Sadakage), daughter (formal wife of Takanashi Sumiyori), Tameshige, others
Nagao Yoshikage served as a sengoku daimyō of Echigo Province during the late Muromachi and Sengoku periods. Yoshikage was the sixth head of the Echigo-Nagao clan and the deputy military governor of Echigo. He was the father of Nagao Tamekage and grandfather of Nagao Kagetora (later known as Uesugi Kenshin).
In 1464, Yoshikage was born as the son of Nagao Shigekage. He served two generations of military governors in Echigo – Uesugi Fusasada and his son, Uesugi Fusayoshi. After the death of Fusasada, Yoshikage held the real power in Echigo, and frequently clashed with Fusayoshi who desired to strengthen the authority of the role of military governor. Nevertheless, Yoshikage remained for nominal purposes the deputy military governor.
In 1504, Fusayoshi’s older brother, Uesugi Akisada (the deputy shōgun for the Kantō) endured a major defeat at the Battle of Tachikawa-no-hara, whereupon Fusayoshi ordered Yoshikage to deploy to the Kantō to support Akisada who confronted a crisis in a confrontation with Uesugi Tomoyoshi of the Ōgigayatsu-Uesugi family. Yoshikage prepared to deploy in order to converge his forces with Akisada. However, after hearing of Akisada’s overwhelming loss on the Tachikawa Plain, he quickly led his men to Hachigata Castle. He then converged with Akisada either on the same evening of the battle or the following day. Upon hearing this news, Tomoyoshi withdrew to Kawagoe Castle. Akisada and Yoshikage then surrounded Kawagoe Castle. In a letter sent the following year, Akisada noted to Satake Yoshikiyo (the military governor of Hitachi Province) that Yoshikage would arrive after the onset of winter. The timing was based on the supposition that Imagawa Ujichika and Hōjō Sōun would be unaware of the arrival of Yoshikage’s reinforcements after Ujichika and Sōun had withdrawn to Kamakura, recuperated at the Atami hot springs, and held a Buddhist memorial service for the war dead at Sōun’s home base of Nirayama Castle.
Yoshikage ardently convinced Akisada that because Tomoyoshi’s soldiers were taking a rest, it gave them a compelling opportunity to attack, so the forces prepared to deploy. The allied forces of Akisada and Yoshikage led by forces from Echigo then launched a sudden attack against Kawagoe Castle. While his men rested, Tomoyoshi plotted to eliminate Akisada. Soon thereafter, Tomoyoshi collided at Uwado with the opposing forces, killed Nagao Higorō, and thwarted the attack. Yoshikage did not appear to fear Tomoyoshi, and in that spirit, laid siege to Hatsuzawa Castle, and the day after killed Nagai Hironao, the lord of the castle, who had been allied with the Ōgigayatsu-Uesugi family. He then installed Mita Ujimune as the new lord of the castle and proceeded to attack and topple Sanada Castle, capturing as a prisoner Ueda Masatada, the deputy military governor of Sagami Province who had also been allied with the Ōgigayatsu-Uesugi family. This severed the territory of the Ōgigayatsu-Uesugi from the Imagawa and Hōjō territories. In the following year of 1505, the allied forces of Akisada and Yoshikage once again laid siege to Kawagoe Castle. Owing to a shortage of defenders, Tomoyoshi surrendered after several months, drawing to a close the Chōkyō War.
In the ninth month of 1506, Yoshikage was requested by Hatakeyama Hisanobu to deploy to Etchū for a battle against the Ikkō-ikki, but died in action at the Battle of Hannyano. This was believed to have been the result of betrayal by Jinbō Norimune, the deputy military governor of Etchū.