Lifespan: Keichō 3 (1598) to 1/3 of Keian 2 (1649)
Title: Junior Fifth Rank (Lower), Governor of Kawachi, Governor of Izu
Domain: Second lord of Hitachi-Shishido; lord of Mutsu-Miharu
Father: Akita Sanesue
Mother: Enkōin (daughter of Hosokawa Akimoto)
Siblings: Toshisue, Suetsugu, Suenobu, Suenaga, Suenori, sister (wife of Araki Takatsuna), sister (formal wife of Tsugaru Nobutake)
Wife: [Formal] Eijuin (daughter of Matsudaira Nobuyoshi)
Children: Morisue, Suehisa, daughter (formal wife of Shinjō Naonaga), daughter (formal wife of Uemura Tadatomo)
Akita Toshisue served as a daimyō during the early Edo period. He was the lord of the Hitachi-Shishido domain and, later, the Mutsu-Miharu domain. Toshisue was the third head of the Akita clan.
In 1614, at the Winter Campaign of the Siege of Ōsaka, Toshisue deployed as a member of the Edo bakufu army. Thereafter, he loyally served the bakufu such as by assisting with construction activities and accompanying Tokugawa Iemitsu (the third shōgun of the Edo bakufu) on travel to Kyōto. Toshisue, however, had a gradual falling out with his father, Sanesue. In 1630, Sanesue was exiled to Asama in Ise Province.
Owing to a pledge of loyalty by Toshisue to the bakufu, in addition to the fact that Toshisue’s mother was a cousin of Sūgen-in, the formal wife of the influential Tokugawa Hidetada, Toshisue was permitted to inherit the headship of the Akita clan whereupon he became the second lord of the Hitachi-Shishido domain. In 1645, after his transfer to Miharu Castle in the Tamura District of Mutsu Province with a fief of 55,000 koku, the Akita family continued to serve the Edo bakufu until the end of the Edo period.
On 1/3 of Keian 2 (1649), while on duty at Ōsaka Castle, Toshisue died, preceding the demise of his father, at the age of fifty-two. Toshisue was succeeded by his eldest son, Akita Morisue.