During the middle of the eleventh century, two powerful families existed in the area; the Abe clan (Oshu [Mutsu province]) ruled Mutsu Province, and the Dewa Kiyohara clan ruled Dewa Province.
11世紀半ば、陸奥国には安倍氏(奥州)、出羽国には出羽清原氏という強力な豪族が存在していた。