Truth that lies in the mists of ancient legend

Often, at such times, it seemed that among the ordinary people the legend had become more important than the history. The retelling of the story in the folk tradition had produced its own narrative, far more strange and wonderful than mere historical fact, but still in a mysterious way reflecting some essence of the original story. Such experiences set me thinking about myths in general, hero stories and legends, and the way they grow over time, and are passed on - and their relation to so-called "real" history. The BBC series that started on Friday is the result of those musings.

The tales in our films come from some of the world’s richest myth- making traditions: Indian, Greek, Arabian and Jewish. The journeys take us to some extraordinarily exotic places - Eritrea, Ethiopia and the Yemen, Nepal and Tibet, Georgia and the mountains of the Caucasus. But it is the myth from the Celtic world which is perhaps the most famous and evocative of the lot: the tale of King Arthur and the Knights of the Round Table.

Now, you might have thought that Arthur was a field too well-trodden for anything new to be said. Everybody has their take on where legends came from, and whether there is any history in them, but nothing new has emerged on the "historical Arthur" over the past 30 years. My own feeling is that the story of Arthur is almost entirely the creation of story-tellers in the British Isles, later embellished by great French and German poets of the Middle Ages. The doyen of the Arthur inventors, Geoffrey of Monmouth in the 1130s, fittingly wrote within yards of the Oxford suburb where The Lord of the Rings, The Chronicles of Narnia, Alice in Wonderland and more recently Philip Pullman’s His Dark Materials were written: and Geoffrey is nearer to them than to any historian. With Arthur, then, don’t think history - think story-tellers.

That said, though, was there a historical kernel? If there was, scholars these days are more and more drawn to a Scottish connection. The first written version of the legend, by Nennius in the early ninth century, claims Arthur was a British hero fighting against the Saxons at the time after the fall of the Roman Empire.

In this first appearance he is already a mythic figure, a Dark Age Che Guevara shading into medieval Superman. Nennius gives Arthur a list of 12 battles which, like other such lists in early Welsh poetry, is drawn from different times and places: but some are obviously northern: the Caledonian forest clearly lies to the north of Hadrian’s Wall; another may be High Rochester in the Cheviots. Even more interesting in the northern connection is the tenth-century Welsh Annals’ mention of the battle where an "Arthur" was killed, along with a Medraut who sounds very much like a prototype of Mordred, Arthur’s eventual betrayer. The name of the battle is Camlann, which if it is to be found in any surviving Roman British placename appears to be Camboglanna: the "crooked bank" - Castlesteads Roman fort on Hadrian’s Wall: a fort that we know was occupied well into the post-Roman twilight perhaps by some Border warlord.

This area between the wall, the Clyde and the Forth is also where the earliest old Welsh poetry derives from: the poems of the bards Aneirin, Taliesin, and interestingly enough, Myrddin "the Wild", the wandering fugitive whom later tradition turned into the prophet and magician Merlin.

All of which might suggest that the shadowy beginnings of the tale might lie in a northern bardic tradition recording battles fought in the Borders between Saxons, Picts, Scots and Cumbrians.

The early Welsh poems allow us to glimpse the real world of Dark Age north British leaders in their feasting halls. They wore golden torcs and cloaks of beaver skin, drank "pale mead" from gilded cups and fought with "stained swords and bristling spears"; boasting, so the poets said, that they would "rather be flesh for wolves than go to the altar to wed": a suitably gritty take on the tale.

But was there a real Arthur? I’d put my money on one of the most famous early Scottish texts: the biography of St Columba by Adomnan of Iona. There, Adomnan tells of a tragic battle, perhaps back in the 580s, in the time of Aidan, the first king of the Dal Riada Scots to really emerge from myth. In the battle, Aidan’s eldest son is killed by a border people known as the Miathi. His name is Artuir.

This Arthur is the genuine article - recorded in an excellent early-eighth century manuscript, so unmediated by the fakers and the myth-makers. And perhaps it’s not stretching the imagination too far to picture a bard in the court of Dal Riada singing of the tragic victorious battle prophesied by St Columba where King Aidan’s heir died fighting with his brothers and heroes of his warband?

That’s just a guess, of course. But in the end, the power of the myth, like all great myths, doesn’t depend on literal historical truth. The perennial vitality of the Arthur legend comes from its great symbols - like the Grail, mystical and ultimately unattainable - and its timeless themes: the quest, the pure knighthood, the fatal union of adulterous love, the tragedy of civil strife, and the ambiguous majesty of kingship itself. All these themes had a fantastic appeal to medieval people, and to the Victorians. And they still do to us today.

Michael Wood is a writer, broadcaster and film-maker. His new series In Search of Myths and Heroes continues on Friday on BBC2.