Bertelot

Bertelot was the brother of the despised Breuse Sans Pitie (Breuse the Pitiless), whom Bertelot often accompanied on his marauding.

Sir Bliant, defending Lancelot from the brothers while Lancelot was mad, struck off Bertelot's hand.

It is possible, but unlikely, that Bertelot could be identified with Sir Bertholai of the Vulgate.