Originally, the Ou region (Mutsu Province and Dewa Province) was placed under the direct control of Kamakura-fu, but the Date clan became a member of Kyoto fuchishu, a direct retainer of Muromachi bakufu, amid a deepening confrontation between Muromachi bakufu and Kamakura-fu, and strategically maneuvered Kamakura-fu in the Oei War of 1413 (also called a Rebellion of Mochimune DATE).
そもそも、奥羽は鎌倉府の管轄ではあったが、幕府と鎌倉府の対立が次第に深まると伊達氏は幕府直属の京都扶持衆となり、1413年の応永の乱では鎌倉を牽制している（伊達持宗の乱とも）。