King Arthur and King Cornwall

"King Arthur and King Cornwall" is an English ballad surviving in fragmentary form in the 17th-century Percy Folio manuscript. An Arthurian story, it was collected by Francis James Child as Child Ballad 30. Unlike other Child Ballads, but like the Arthurian "The Boy and the Mantle" and "The Marriage of Sir Gawain", it is not a folk ballad but a professional minstrel's song. It is notable for containing the Green Knight, a character known from the medieval poems The Greene Knight and the more famous Sir Gawain and the Green Knight; he appears as "Bredbeddle", the character's name in The Greene Knight.

"King Arthur and King Cornwall" occurs in a damaged section of the Percy Folio; about half of each page was ripped out to start fires. As such, the ballad is missing about half of its content, though some of the missing material can be deduced from context. Apparently after bragging about the excellence of his famed Round Table, King Arthur is told by Guinevere that another king has an even better one. Arthur and his company leave their kingdom (here Brittany rather than Great Britain) in disguise searching for this king, and eventually come to Cornwall, where the resident monarch offends them with a series of boasts about his magical items, the child he fathered on Guinevere, and Arthur's comparative mediocrity. All go off to bed, and the Knights of the Round Table make a series of vows against Cornwall's boasts, such as Gawain's declaration that he will make off with Cornwall's daughter.

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