Gilierchino
One of the various names given to the father-in-law of Tristan. He was called Havelin by Eilhart and Jovelin by Gottfried, while this variation appears in the Italian Tavola Ritonda, in which he replaces Hoel.
The king of Solona in Brittany and father of Isolde of the White Hands, Gilierchino went to war with his nephew, Count Albroino of Gippa. When Tristan saved his lands by defeating Albroino, Gilierchino forced him to accept the crown of Brittany.
Source
La Tavola Ritonda | 1325–1350