The Matter of Britain is a name given collectively to the legends that concern the Celtic and legendary history of the British Isles, centering around King Arthur and the knights of the Round Table. The twelfth century French poet Jean Bodel created the name in a chanson de geste he wrote, the Chanson de Saisnes, in which appear the lines:
Ne sont que iij matières à nul homme atandant,
De France et de Bretaigne, et de Rome la grant.
(There are but 3 literary cycles that no one should be without: the matter of France, of Britain, and of great Rome.)
The name distinguishes and relates the Matter of Britain from the mythological themes taken from classical antiquity, the "matter of Rome", and the tales of the paladins of Charlemagne and their wars with the Moors and Saracens, which constituted the "matter of France." While Arthur is the chief subject of the Matter of Britain, other lesser-known legendary history of the British Isles, including Brutus of Britain, Old King Cole, King Lear, and Gogmagog is also included in the subjects covered by the Matter of Britain: see King of the Britons.