Redcross Knight

The Redcross Knight is a strong knight who once killed a dragon. He has long blond hair and wears a white mantle with a red cross on it. He was one of the fighters present at world's end keep when the last boat escaped the homelands. He held an entire keep by himself for most of the day, until he was roasted alive by a dragon in the Adversary's army.

Source material
The Redcross Knight is a character from Edmund Spenser's The Faerie Queene, in which his name is written as Redcrosse Knight. In The Faerie Queene, the Redcrosse Knight is claimed to be Saint George, and Boy Blue's claim that he once killed a dragon seems to validate this connection in Fables as well.