CHARLES OLYVER means Charlemagne's Oliver and refers to Oliver, Roland's companion and friend in La Chanson de Roland (twelfth century). In the poem Oliver is always wise, while Roland is brave. Oliver and Roland courageously try to lead the French host in their attempt to fight their way out of the ambush into which the Saracens have trapped them in the Pass of Ronscevalles. The French host has been betrayed to the enemy by Roland's stepfather Ganelon.
The Monk says that Oliver de Mauny, a French nobleman who betrayed Don Pedro of Castille to his brother Don Enrique, cared not for honor like Charlemagne's Oliver, but was a "Genylon-Olyver," that is, a traitor, MkT 2387-2390. Froissart records the story in Chronicles I.245. [Genylon-Olyver: Petro1: Rowland]
Charles Olyver is the ME possessive case and occurs medially, MkT 2387.