Meigetsu-in Temple was founded by Yamanouchi Uesugi family progenitor and Kanto Kanrei (Shogun's deputy in the Kanto region) Norikata UESUGI, who invited Misshitsu Shugo to serve as head priest.
山ノ内上杉家の祖、関東管領上杉憲方は密室守厳を開山として、明月院を開創した。