Lifespan: Genki 2 (1571) to 1/5 of Genna 6 (1620)
Other Names: Matasuke
Title: Bizen-no-kami (Governor of Bizen)
Lord: Shimazu Yoshihisa
Father: Shimazu Yoshitora
Mother: Ohira (daughter of Shimazu Yoshihisa)
Siblings: Sister (wife of Shiki Chikahiro), Tadatoki, Tadachika, Tadakiyo, Tadahisa, Tadatomi, Tadatoyo, sister (wife of Ogawa Arisue) (?)
Wife: Ritsuno-dono (Catarina, daughter of Minayoshi Tsuguyoshi)
Children: Son, daughter
Adopted Children: Myō (dowager of Kiire Tadamasa)
Shimazu Tadakiyo served as a bushō from the Sengoku to early Edo periods.
In 1571, Tadakiyo was born as the third son of Shimazu Yoshitora.
In 1593, his older brother, Shimazu Tadatoki, stirred the anger of Toyotomi Hideyoshi for failing to deploy with Shimazu Yoshihiro for the Bunroku Campaign on the Korean Peninsula. Tadatoki, along with his younger brothers, Tadatomi and Tadatoyo, were turned-over to the custody of Konishi Yukinaga at Uto Castle in Higo Province to be incarcerated. Tadatoki was then removed from his position.
Meanwhile, Tadakiyo wed Ritsuno-dono (with a baptismal name of Catarina), the daughter of Minayoshi Tsuguyoshi, a retainer of Yukinaga, and was blessed with a son and daughter. This was a second marriage for his wife, who brought along a daughter named Myō. Later, she became a dowager of Kiire Tadatsugu.
In 1600, after the Battle of Sekigahara, owing to Konishi Yukinaga having served on the Western Army, Katō Kiyomasa of Kumamoto occupied Uto in the former territory of Yukinaga. Tadakiyo and others were apprehended by the Katō family and transferred to Kumamoto. After his grandfather, Shimazu Yoshihisa and Shimazu Tsunehisa negotiated with the Katō family and, on 12/3 of Keichō 14 (1609), Tadakiyo was able to return with his two children to Satsuma Province. Thereafter, his son succeeded Niiro Hisamoto and adopted the name of Niiro Tadakage. His daughter became a consort of Shimazu Iehisa and bore Shimazu Mitsuhisa (the second lord of the Satsuma domain), Hongō Hisanao, and Shimazu Tadanori, thereby raising the status of the family. In 1620, however, Tadakiyo died of illness and was buried at the Kōkoku Temple in the town of Hiyamizu. Other than Tadakage, Tadakiyo did not have any sons so he was succeeded by Niiro Hisamoto, the second son of Niiro Hisamichi. (Hisamichi was the grandson of Tadakage.)
Ritsuno-dono (Catarina) was a Christian convert and, after the practice of Christianity was prohibited, she protected many of the faithful in their territory, frequently receiving warnings from the domain. After the death of Tadakiyo, in 1633, Catarina was sent into exile at Ōnagano on Tanegashima. She lived in confinement under the supervision of Tanegashima Tadatoki. In 1639, via Ise Sadamasa, she converted to the Hokke school of the Nichiren sect of Buddhism, but this was regarded as superficial and not recognized as a repudiation of her Christian faith. That same year, her daughter from a previous marriage (the wife of Kiire Tadamasa) and her daughter were exiled to the same island. In 1649, she died. Despite her exile, owing to her affinity to the lord of the domain, she was not treated roughly, with persons occasionally checking on her well-being. At the time of her demise, a messenger of Shimazu Mitsuhisa (her grandson and lord of the domain) made a votive offering of incense.