Galegantins
Lancelot’s maternal grandfather; the father of Elaine and Evaine.
After his daughters were married, Galegantin retired to a seaside hermitage and became a holy man. Lancelot visited him during the Grail Quest, on his way to Corbenic (Carbonek), and Galegantin tried to persuade him to end his affair with Guenevere.
Source
Post-Vulgate Queste del Saint Graal | 1230-1240