Claude Auclair was one of the most notable realistic French comic authors from the 1960s and 1970s, best known for his comics with science fiction and post-apocalyptic themes. He was born in La Barre-de-Monts in the Vendée, a province south of Brittany. He settled in Nantes in 1953, where he studied Fine Arts. He worked as a theater decorator until 1967, and then traveled around the Méditerranée. Auclair started out as an illustrator for science fiction publications by Éditions OPTA, such as Galaxie-Bis and Fiction. He published his first comic story in Phénix in 1968.
He was pushed by fellow artists Moebius and Philippe Druillet to begin an association with Pilote magazine in 1970. He initially drew several short stories, and eventually started the post-apocalyptic 'Jason Muller' series. When editor-in-chief René Goscinny cancelled this series, Auclair moved over to Record, where he created 'Catriona McKilligan', an historical series about the Scottish revolt, with textwriter Jacques Acar.
While still working for Pilote, Auclair had his first publications in Tintin, such as the western 'La Saga du Grizzly' and 'Les Naufragés d'Arroyoka' with Greg. For Tintin, he also made his most famous series, 'Simon du Fleuve', in 1973, for which he did both text and artwork.