Shizukuishi Akisada served as a bushi during the Sengoku period. Akisada was the lord of Shizukuishi Castle in Mutsu Province.
The Shizukuishi were an illegitimate branch of the Shiba clan, members of the Ashikaga clan having the same founder as the Ashikaga shōgun family, descended from the Kawachi-Genji lineage who were a branch of the Seiwa-Genji.
His father, Shiba Akitaka (a sengoku daimyō in Mutsu), ruled the village of Shizukuishi after garnering it from the Nanbu clan and became the lord of Shizukuishi Castle. Owing to his being a member of the Ashikaga clan with the same founder as the Ashikaga shōgun family, he was respectfully called within the family as well as externally as Shizukuishi gosho, or Prince Shizukuishi.
His grandson (or son) was Shizukuishi Hisaaki.