During the Meitoku War started by Mitsuyuki YAMANA in 1391, the Mitoya clan seceded from the Yamana clan and participated in the punitive force against it under the command of the government headed by a shogun.
明徳2年（1391年）の山名満幸の明徳の乱では山名氏の傘下を離れ、幕府の指示に従って、山名氏討伐に傘下している。