Having been handed down in Japan from old times, Mishaguji is a kami (of Shinto) whose origin is not very clear. This kami is also called Mishaguchi or Shaguji and a number of kanji expressions are used, such as 御左口 and 赤口.
Mishaguji belief is widely distributed in eastern Japan, and it is said that Mishaguji is a kami in snake form with stones and trees being its main yorishiro (object representative of a divine spirit). The pattern of Mishaguji belief varies from region to region, with Mishaguji's deity being sometimes fused with the deity of local and other types of kami. This belief is considered to have existed from the Jomon period based on the fact that objects of worship for Mishaguji and things which were identical to Mishaguji's yorishiro were found at a number of Jomon period sites located in the area where Mishaguji belief has prevailed.
People in Suwa region say that Mishaguji takes the form of a white snake, perhaps because it was fused with the Soso deity which was a snake kami of Suwa. Other kanji allocated to express Mishaguji include 御社宮司 and 御左口.
In Moriya-jinja Shrine where this kami was enshrined, it was regarded as a kami who enters into a Shinto priest and provides divine messages. It is also said that Mishaguji was worshipped by mountain people, such as Matagi (the hunting communities in Tohoku mountains).