Although it reached the high watermark in the Muromachi period, it came to decline due to frequent inter-clan conflicts, such as one with the Tendo clan, and Yoshisada MOGAMI was defeated by the Date clan in the battle of Hasedo-jo Castle in 1514 and became under control of the Date clan temporarily.
室町時代に最初の最盛期を迎えたが、やがて天童氏など同族内の争いが絶えず起こったために衰退し、最上義定の頃の1514年(永正11)には伊達氏と長谷堂城で戦って敗北し、一時は伊達氏の配下になる。