Bercilak

The Green Knight is a character of the 14th-century Arthurian poem Sir Gawain and the Green Knight and the related medieval work The Greene Knight. His true name is revealed to be Bertilak de Hautdesert (an alternate spelling in some translations is "Bertilak" or "Bernlak") in Sir Gawain, while The Greene Knight names him "Bredbeddle". The Green Knight later features as one of Arthur's greatest champions in the fragmentary ballad "King Arthur and King Cornwall", again with the name "Bredbeddle". In Sir Gawain and the Green Knight, Bercilak is transformed into the Green Knight by Morgan le Fay, a traditional adversary of King Arthur, in order to test his court. In The Green Knight he is transformed by a different woman for the same purpose. In both stories he sends his wife to seduce Gawain as a further test. "King Arthur and King Cornwall" portrays him as an exorcist and one of the most powerful knights of Arthur's court.

In Sir Gawain, the Green Knight is so called because his skin and clothes are green. The meaning of his greenness has puzzled scholars since the discovery of the poem, who identify him variously as the Green Man, a vegetation being of medieval art; a recollection of a figure from Celtic mythology; a Christian symbol; or the Devil himself. The medieval scholar C. S. Lewis said the character was "as vivid and concrete as any image in literature."J. R. R. Tolkien called him the "most difficult character" to interpret in the introduction to his edition of Sir Gawain and the Green Knight. His major role in Arthurian literature includes being a judge and tester of knights, and as such the other characters consider him as friendly but terrifying and somewhat mysterious.

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