He had left posterity, but of them Gildas had no good opinion, as can be readily believed, if his Aurelius Caninus was of their number. To Welsh tradition he became known as Emrys Wledig (Ruler), but confusion arose when he was identified with the Ambrosius of Nennius , the boy hero of the folk tale who confounded the magicians of Vortigern and gave his name to Dinas Emrys , near Beddgelert .
Geoffrey of Monmouth treats the Ambrosius of history with characteristic freedom; he becomes Aurelius Ambrosius , son of Constantine (not the Great ), who is carried off as an infant to Brittany , returns to Britain , is anointed king , and overwhelms Vortigern . He then meets Hengist in battle and slays him; the country is pacified, churches are restored, and law and order re-established.
The complication introduced by Nennius is adroitly solved, for it appears that the wonder-worker was really Merlin , ‘who was also called Ambrosius .’ Thus arose the supposed distinction between ‘ Merlinus Ambrosius ’ and ‘ Merlinus Celidonius .’
Sir John Edward Lloyd, D.Litt., F.B.A., F.S.A. (1861-1947), Bangor
Published date: 1959