For hundreds of years the standard history of Britain was the one supplied by an obscure teacher, writer, cleric - and, later, priest - of dubious Welsh connections. His name was Geoffrey of Monmouth and his words were believed implicitly, from the time of their creation in the 12th century right down to the days of Queen Elizabeth.
Only much later did it become clear that Geoffrey's version of British history came from a range of different sources. These included a ninth century Welsh book of history (written in both Latin and Welsh), the work of monks like Bede and Gildas, the poems of several Welsh bards - and, in particular, his own rather vivid imagination.
Virtually everything about Geoffrey of Monmouth is obscure, even his date of birth. In all probability he was born around the year 1100, possibly in the Marches of Wales. Even that is unclear.
Historia Regum Britanniae
He called himself Geoffrey of Monmouth in his most famous and influential book, Historia Regum Britanniae, a supposed history of Britain's kings. He probably, therefore, had some connection with the Monmouth area and may well have been born there.
The background of his parents is, likewise, also unknown but they may well have come from Brittany with William the Conqueror in 1066. It is unlikely that he had any Welsh blood in him - as was originally believed - and he almost certainly had only a passing acquaintance with the Welsh language. He wrote in Latin, as did most learned men in those days.
For many years it was believed that Geoffrey was a monk or a cleric at the Benedictine Priory in Monmouth but, in fact, he may well only have studied there as a youth. Most of his adult life was actually spent outside Wales.
Certainly he was made secular canon at the Collegiate Church of St George in Oxford and between 1129 and 1151 his name, along with that of the Archdeacon of Oxford, appeared on six different charters for the Oxford area.
Bishop of St Asaph
On 21 February 1152 Geoffrey of Monmouth was appointed Bishop of St Asaph. Amazingly, he had only been ordained as a priest some two weeks before. The new Bishop probably never went near St Asaph as the rebellion of Owain Gwynedd was raging at the time and to venture to that particular part of north Wales would, in all honestly, have meant death and disaster.
Geoffrey died somewhere around December 1155, already acknowledged as a major historian but, in reality, one of the greatest legend makers Wales and Britain had ever seen.
Dedicated to Robert, Earl of Gloucester, Historia Regum Britanniae remains his best known work. It purported to be a true history of Britain and of her kings from the time of Brutus - a descendant of Aeneas of Troy, not the Shakespearean character - through the Roman invasion of Julius Caesar to the reigns of Leir and Cymbeline (that one DID later become a Shakespearean figure).
Creating a legend
Above all his Historia included the character for whom Geoffrey is always best remembered, King Arthur. His work on creating the legend - arguably a necessity in a period of trouble and strife when the country was desperately seeking to return to happier, more peaceful times - certainly began the popularity of the Arthurian legend. Later kings and historians took the legend and adapted it to their own needs but it undoubtedly began with Geoffrey of Monmouth.
Unfortunately, Geoffrey did not confine himself to the true historical facts around the character of Arthur. After all, like most story tellers - and that is how we should remember him, as a very good story teller - Geoffrey was not going to let the truth get in the way of a great tale.
It remains a sad fact but if Geoffrey had told the real story of the Romano-British warrior chief who fought against the Saxon invaders we might have had more of a grasp on our history during those troubled years. As it was, his work - his fantasy work - on Arthur and Merlin opened the way to a whole raft of Arthurian fantasies.
Geoffrey's earliest book was also on the Arthurian theme. The Prophesies of Merlin supposedly contained speeches and comments made by the great magician, translated by Geoffrey from some obscure language which he never identified. Clearly he was fascinated by the Arthurian topic.
Geoffrey of Monmouth remains an incredible character, in his way as compelling as the stories he created and the people he wove into them. View him as a man of his time - but certainly not as an accurate and detailed chronicler of Britain's history.