It is believed that the story was based on "Taiheiki" (The Record of the Great Peace) and "Masukagami" (The Clear Mirror) which stated that Tokiyori HOJO, the regent of the Kamakura bakufu (the Japanese feudal government headed by shogun), became a monk in 1256 after suffering from illness and traveled around Japan with his identity concealed.
これは鎌倉幕府執権だった北条時頼が康元元年（1256年）に病でたおれ、出家したときに自らの地位を隠し諸国を旅したことが記されている太平記や増鏡を元にしたものだとされる。