a traditional story accepted as history; serves to explain the world view of a people
source: WordNet 3.0
A story of great but unknown age which originally embodied a belief regarding some fact or phenomenon of experience, and in which often the forces of nature and of the soul are personified; an ancient legend of a god, a hero, the origin of a race, etc.; a wonder story of prehistoric origin; a popular fable which is, or has been, received as historical.