Geoffrey of Monmouth

Geoffrey of Monmouth (circa 1100-54), Welsh writer and ecclesiastic. He was the author of Historia Regum Britanniae (1136?; History of the Kings of Britain), a work purporting to delineate the lives of British kings from Brutus the Trojan, the mythical progenitor of the British people, to Caedwalla, king of North Wales (reigned about 625-34). Although the work is known to have existed as early as 1136, copies now extant are believed to date from 1147. The history is based on the writings of the early British chroniclers Gildas and Nennius and on popular legends, but includes much fictitious material. The ninth, tenth, and eleventh books, of the twelve constituting the work, contain the first extensive collection of tales dealing with King Arthur that afterward formed the basis for the Arthurian legend. A Norman translation of the Historia by the Anglo-Norman poet Wace was used in English about 1205 by Layamon, an English priest.

For his history, Geoffrey earned the favor and patronage of Robert, earl of Gloucester; as a result, he was named archdeacon of Llandaff about 1140 and bishop of Saint Asaph in 1152.