Definition of Geoffrey of Monmouth in English:
Geoffrey of Monmouth
(c.1100–c.54), Welsh chronicler. His "Historia Regum Britanniae" (c.1139; first printed in 1508), an account of the kings of Britain, was a major source for English literature, especially for the tales of King Arthur.
Geoffrey of Monmouth/ˌjefrē əv ˈmänməTH/