Lifespan: Kōji 2 (1556) to 2/8 of Genna 7 (1621)
Clan: Yura → Ashikaga-Nagao
Lord: Takigawa Kazumasu → Gohōjō clan → Satake Yoshinobu
Father: Yura Narishige
Siblings: Yura Kunishige, Watarase Shigeaki, Akinaga, sister (formal wife of Narita Ujinaga), sister (wife of Kuroda Naoyuki)
Wife: Daughter of Nagao Masanaga
Children: Tomokage, Tomonaga
Nagao Akinaga served as a bushō from the Sengoku to early Edo periods. He served as the head of the Ashikaga-Nagao clan based in Kōzuke Province.
In 1556, Akinaga was born as the third son of Yura Narishige. His mother was Myōin-ni. He wed the daughter of Nagao Masanaga (later known as Kagenaga), the head of the Ashikaga-Nagao clan. After the demise of Kagenaga in 1569, Akinaga inherited the headship of the clan. Kagenaga’s base at Tatebayashi Castle, however, was granted to another son-in-law named Hirota Naoshige.
In 1582, Akinaga, along with his older brother, Yura Kunishige, served Takigawa Kazumasu. Later, he submitted to the Gohōjō clan. In 1585, Akinaga engaged in a dispute with Sano Munetsuna, the head of the Sano clan of Shimotsuke Province and killed him. In 1590, during the Conquest of Odawara led by Toyotomi Hideyoshi, Akinaga holed-up in Odawara Castle and fought against the assault, so, after the demise of the Hōjō clan, his landholdings were confiscated and he became a rōnin, or wandering samurai. For a while, he served Satake Yoshinobu of Hitachi Province but, thereafter, wandered again. His son, Nagao Tomokage, served Doi Toshikatsu, a hereditary daimyō in Shimōsa Province, later becoming a chief retainer.