Lifespan: Kyōtoku 3 (1454) to 3/10 of Tenbun 15 (1546)
Name Changes: Iekane → Tsunatada
Other Names: Magokurō
Rank: bushō, sengoku daimyō
Title: Governor of Yamashiro
Lord: Shōni Sukemoto, Shōni Fuyuhisa
Father: Ryūzōji Yasuie
Siblings: Taneie, sister (wife of Uchida Sakyō-no-jō), Iekazu, Chōkaku, Ōinosuke, Iekane, Tenkō
Ryūzōji Iekane served as a bushō and sengoku daimyō of Hizen Province during the Muromachi and Sengoku periods. Iekane was the lord of Mizugae Castle and the great-grandfather of Ryūzōji Takanobu.
In 1454, Iekane was born as the fifth son of Ryūzōji Yasuie, the thirteenth head of the Ryūzōji clan, kokujin, or provincial landowners, in Hizen.
Initially, Iekane founded a cadet family known as the Mizugae-Ryūzōji. Owing to internal conflict and the early death of its lord, the Muranaka-Ryūzōji (the main branch of the clan) lost influence so, as one of the elders of the clan, Iekane supported the main branch.
Obstinate and courageous, Iekane soon took control of the Muranaka-Ryūzōji and rose to become the head of retainers of his lord, the Shōni clan. In 1530, Ōuchi Yoshitaka assigned 10,000 soldiers to Sugi Okikazu to invade Hizen, but Iekane repelled them at a tributary to the Chikugo River. This event is known as the Battle of Tadenawate.
After this battle, Yoshitaka recognized Iekane’s power and recommended to him that he abandon the Shōni and follow the Ōuch clan instead. Iekane was a tozama, or outsider among retainers (the Ryūzōji were former retainers of the Kyūshū-Chiba clan previously ousted by the Shōni) and when the Ōuchi attacked his lord, Shōni Sukemoto, Iekane did not actively support him. In the end, Sukemoto was compelled to take his own life and Iekane was suspected of having betrayed his lord. Thereafter, however, Iekane served Sukemoto’s son, Shōni Fuyuhisa, and it is uncertain whether he desired to rebel against the Shōni.
In the second month of 1538, Iekane underwent the rites of tonsure and adopted the name of Tsunatada.
In 1545, Baba Yorichika, a retainer of the Shōni clan, became upset that Tsunatada did not actively support Sukemoto during the attack which he likened to a rebellion resulting in the death of his lord. He then devised a plot whereby two of Tsunatada’s sons and four of his grandsons were all slaughtered. Tsunatada himself narrowly escaped to Chikugo Province for protection under Kamachi Akimori, the lord of Yanagawa Castle. As a result of being over ninety years old, Tsunatada survived without being subject to rigorous questioning.
In 1546, Tsunatada pushed his old self with the support of the Kamachi clan to raise aims in a bid for a revival. Nabeshima Kiyofusa acted in concert with him, killing Yorichika and achieving a revival of the Ryūzōji clan. He had his great-grandson, Tanenobu (later known as Ryūzōji Takanobu), return to secular life and, after entrusting affairs to him, died soon thereafter.