This article will use close textual analysis in order to examine the role played by prophecy and the supernatural in Geoffrey of Monmouth’s Historia Regum Britanniae. This immensely popular and influential work includes three instances of prophetic vision: the first comes early in the narrative in a pagan setting when Bruto, the mythical founder of Britain, receives a message from the goddess Diana, in a dream; the last vision is a divine revelation from an angel to the last Cristian king of Britain, Cadwallader; during the peak of the narrative, king Arthur also experiences a dream-vision. 
