[Len Parker]

Thomas Malory

Soon Balin asked a knight, Is there not a knight in this court whose name is Garlon? Yonder he goeth, said a knight, he with the black face; he is the marvellest knight that is now living, for he destroyeth many good knights, for he goeth invisible. http://www.sacred-texts.com/neu/mart/mart040.htm

I'm not sure whether Sir Garlon having a black face is meant to be part of the enchantmet that enables him to ride invisibly or he is an actual black man. There is no mention of his his brother king Pellam being black.