Geoffrey of Monmouth (Latin Galfridus Monemutensis, d. c. 1155) was a writer and cleric best known for his Historia Regum Britanniae ("History of the Kings of Britain"), an imaginative and often fanciful account of the kings of Britain from its foundation by Brutus, great-grandson of the Trojan hero Aeneas, the legendary ancestor of the Romans, to Cadwaladr, a 7th century king of the Welsh kingdom of Gwynedd, and including an early and influential account of the reign of King Arthur.
Judging by his name, Geoffrey was born, or at least brought up, in Monmouthshire in south Wales. Later tradition names his father as Arthur. His signature appears on six charters connected with religious foundations in the Oxford area dated between 1129 and 1151, two of which bear the title magister (master, teacher). He may have been an Augustinian canon of the secular college of St. George's, where Archdeacon Walter was Provost, during much of this time. It was during his time at Oxford he produced his literary work.
In 1151 he became Bishop Elect of St. Asaph in north Wales. He was ordained as a priest in February 1152, and was consecrated by Archbishop Theobald at Lambeth a week later. He was one of the bishops who witnessed the 1153 Treaty of Westminster between King Stephen and Henry Fitz-Empress. He died, according to the Welsh Chronicles, in 1155, apparently never having visited his diocese.
Geoffrey's first work was apparently the Prophetiae Merlini ("Prophesies of Merlin"), which he claimed to have translated into Latin at the request of Alexander, Bishop of Lincoln. These prophesies, and the dedication to Bishop Alexander, were later incorporated into a longer work, the Historia Regum Britanniae, which he finished c. 1136.
The Historia also claims to be a translation, from "a certain very ancient book in the British language" given to Geoffrey by Walter, Archdeacon of Oxford, but few scholars take this seriously, or at least at face value. Geoffrey probably drew on Welsh sources now lost, but much of his material can be identifiably traced to Latin sources such as Gildas, Bede and the 9th century Historia Brittonum. Several Middle Welsh versions of the Historia exist, but all are later than Geoffrey and are considered translations or adaptations of his work.
The Historia begins with the foundation of Britain by the Trojan exile Brutus, takes in the earliest known source of Shakespeare's story of King Lear and his three daughters, the sack of Rome by Belinus and Brennius (based on the historical sack of Rome by a Gaul named Brennus in 390 BC), garbled accounts of the Roman invasions by Julius Caesar and Claudius and the Carausian Revolt, the departure of the Romans, the rise of Vortigern and the coming of the Saxons. The reign of Arthur is related in detail, almost taking over the work, which concludes with the decline of the Britons and the final victory of the Saxons. As history it is virtually worthless, but does contain surprising nuggets of truth. For example, he tells of how a Roman legion was decapitated at London, their heads thrown into a river called the Gallobroc: in the 1860s a large number of human skulls, and almost no other bones, were found in the river Walbrook in London in excavations led by General Augustus Pitt-Rivers.
In c. 1148 Geoffrey wrote a third work, the Vita Merlini ("Life of Merlin"), written in Latin verse.
More than 200 manuscripts of the Historia Regum Britanniae are known, making it the medieval equivalent of a bestseller. The earliest comments on it are critical. William of Newburgh wrote c. 1190 that "whatever Geoffrey has written, subsequent to Vortigern, either of Arthur, or his successors, or predecessors, is a fiction, invented either by himself or by others, and promulgated either through an unchecked propensity to falsehood, or a desire to please the Britons".[1] Giraldus Cambrensis wrote c. 1191 of a man possessed by demons:
"If the evil spirits oppressed him too much, the Gospel of St. John was placed on his bosom, when, like birds, they immediately vanished; but when that book was removed, and the History of the Britons, by Geoffrey Arthur, was substituted in its place, they instantly reappeared in greater numbers, and remained a longer time than usual on his body and on the book."[2]
Despite these damning verdicts, Geoffrey's work was extremely influential in the medieval and Renaissance periods, as both a historical and a literary work. It was translated into Norman French verse by Wace (the Roman de Brut) in 1155; into Middle English verse by Layamon (the Brut) in the early 13th century; and into three different Welsh prose versions by the end of the 13th century. The Arthurian section undoubtedly influenced the development of Arthurian literature on the continent, including the Lais of Marie de France and the romances of Chrétien de Troyes.