Gornemant was Percival's mentor in Arthurian legend. He is mentioned in a few early romances, but achieves prominence in Chrétien de Troyes' Perceval, the Story of the Grail, where he instructs the young hero in the ways of knighthood. Percival is a quick learner when it comes to combat, but he does not know how to behave like a knight, so Gornemant tells him not to ask so many of his naive questions, hoping to make the boy look like less of a Welshhick. This has grave implications later when Percival takes the advice too much to heart and refrains from asking the Fisher King about the Grail.
Gornemant's niece is Blanchefleur, whom Percival later marries after successfully defending her city against attackers.