Lifespan: Ei1/16 of Tenshō 10 (1582) to 6/5 of Kanei 9 (1632)
Other Names: Matahachirō (childhood)
Rank: bushō, daimyō
Title: Junior Fifth Rank (Lower), Director of the Imperial Palace Keeper’s Bureau
Domain: Shimōsa-Omigawa → Mikawa-Fukōzu → Mikawa-Yoshida
Lord: Tokugawa Hidetada → Tokugawa Iemitsu
Father: Matsudaira Ietada
Mother: Second daughter of Mizuno Tadawake
Siblings: Tadatoshi, Tadakazu, Tadashige, Tadataka
Wife: [Formal] Daughter of Matsudaira Iekiyo
Children: Tadafusa, Tadasue, daughter (formal wife of Kinoshita Toshiharu)
Matsudaira Tadatoshi served as a bushō and daimyō during the Azuchi-Momoyama and early Edo periods. Tadatoshi was the fifth head of the Fukōzu-Matsudaira family. After serving as the lord of the Omigawa domain in Shimōsa Province and the Fukōzu domain in Mikawa Province, Tadatoshi served as the first lord of the Yoshida domain in Mikawa.
Tadatoshi was born as the eldest son of Matsudaira Ietada, the fourth head of the Fukōzu-Matsudaira family. Beginning in 1596, he served Tokugawa Hidetada. In 1600, he received one of the characters from the name of Hidetada and adopted the name of Tadatoshi.
Later in 1600, during the Siege of Fushimi Castle in the prelude to the Battle of Sekigahara, his father, Ietada, was killed in action so he inherited the territory of Omigawa in Shimōsa. Thereafter, he followed Tokugawa Ieyasu and headed to Shimotsuke Province where he remained behind to prepare defenses against a potential southern advance by Uesugi Kagekatsu. At this time, Tadatoshi sought to join the battle to exact revenge for the earlier loss of his father but was not allowed.
After the war, owing to his contributions in Sekigahara, he was awarded 10,000 koku in the former territory of his ancestors in Fukōzu in Mikawa. In 1612, his fief was increased to 30,000 koku in Yoshida in Mikawa. Tadatoshi served meritoriously in the Siege of Ōsaka. On 6/5 of Kanei 9 (1632), he died at the age of fifty-one. He was succeeded by his eldest son, Matsudaira Tadafusa.
Tadatoshi excelled in renga, or linked-verse poetry, and engaged in exchanges with Satomura Jōha. His works are contained in a compilation of poems.