Only after the Kamakura period, it was specifically described in historical materials: "Mirokunyorai Kanno Shoso" (The selection of the influence of Mirokunyorai) described it for the fist time in 1236.
史料上、明確に現れてくるのは鎌倉時代以降、「弥勒如来感応抄草」の1236年（嘉禎2）である。