After appointed as Mutsu shugoshiki (provincial constables of Mutsu Province), Tanemune DATE drastically increased its influence by adopting Yoshinobu OSAKI in return for solving an internal conflict of the Osaki clan (then-Oshu Tandai), and putting the Osaki clan and later the Mogami clan of Dewa Province under control.
伊達稙宗は陸奥守護職に補任し、奥州探題であった大崎氏の内紛を解決して、大崎義宣を養子に入れて傘下に取り込み、出羽国の最上氏も勢力圏に組み込むなど大きく飛躍した。