However, Ezogashima began to leave from the Ando clan's control, and as a result, in the earlier Sengoku Period the clan degraded practically to a mere local ruling lord in the northern Dewa Province, as particularly the clan had to echo the fact that the Kakizaki clan, who had been the hikan in Ezo, proclaimed its position of Matsumae shugo (military governor of Matsumae) as well as Kaminokuni shugo.
しかし、次第に蝦夷島が安東氏の統制から離れ始め、特に蝦夷において被官であった蠣崎氏が上国守護職に加えて松前守護職を名乗ったことを追認せざるを得なくなるなど、戦国時代(日本)前期には実質上北出羽の一豪族となった。