The first theory is that the expedition of Yoritoshi actually ended as a great success as he insisted, by conquering the regions from Tsugaru Peninsula to Shimokita Peninsula and expanding the ruling of the Imperial Court throughout the Honshu Island.
一つ目は、頼俊の遠征はその主張のように大成功し、津軽半島と下北半島までの本州全土を朝廷の支配下に置いたとするものである。