Wikipedia
Yama-bito
The term "" or sanjin, as understood in Japanese folklore, has come to be applied to a group, some scholars claim, of ancient, marginalized people, dating back to some unknown date during the Jomon period of Japanese history.
The term itself has been translated as "Mountain People", or as Dickins interprets the word, simply, "Woodsman", but there is more to it than that. It is from texts recorded by historian Kunio Yanagita that introduced, through their legends and tales, of the concept of Kamikakushi, or, being "spirited away", into Japanese popular culture.