 His best-selling work is his autobiographical "Le cheval d'orgueil", or "The Horse of Pride", adapted for cinema by Claude Chabrol in 1980, rooted in the Bigoudenn area south of Quimper.This was also published in Breton as "Marh ar lorh", after its success on screen had turned Helias into a national celebrity.He also collected folk tales from his native Brittany and published work on the Breton language and culture.