Matter of Britain
The Matter of Britain (French: matière de Bretagne; Welsh: Mater Prydain; Cornish: Mater Brythain; Breton: Afer Breizh-Veur) is the body of medieval literature and legendary material associated with Great Britain and Brittany and the legendary kings and heroes associated with it, particularly King Arthur. The 12th-century writer Geoffrey of Monmouth's Historia Regum Britanniae (History of the Kings of Britain) is a central component of the Matter of Britain.