Aesclamor
The ruler of the Red City.
A subking probably contemporary at least with Arthur’s early days, if not with his later ones. Esclamor’s territory seems to have been in the neighborhood of the Forest of the Boiling Well.
He forbade a knight named Sir Eloides from marrying his daughter. Eloides did so anyway and, to protect her from Esclamor, he established the Forbidden Hill (Le Tertre Deuee), which was eventually conquered by Lancelot.
Source
Vulgate Lancelot | 1215-1230