A SCOTTISH author is claiming the £50,000 offered by another Scots-born writer to anyone who could disprove his theory that the legendary King Arthur was a Scottish prince known as Arturius.

Adrian Grant from Fife says that his book Arthur: Legend, Logic and Evidence proves comprehensively that Arthur was a war leader – and not a king from near Leeds in modern-day Yorkshire – who went north in the late fifth century to command the Britons of Strathclyde to victories over the Picts and the Scots.

As The National revealed earlier this week, author David Carroll – perhaps ironically, he is from Glasgow but now lives in Yorkshire – is so sure that his Arturius as named in ancient documents is the real King Arthur and that he was Scottish that he was prepared to pay £50,000 to anyone who can prove him wrong.

There is nothing new about spats between authors, especially non-fiction writers, but the difference in this disagreement – conducted most politely, it must be said – is the staggering £50,000 prize should Carroll accept that Grant is correct.

The National can reveal that Grant made his claim after reading our story and that Carroll, while initially rejecting it, has agreed to consider the evidence.

Grant, 70, a retired teacher from Cupar, wrote his book based on his long years of research into the Arthurian tales, relying on original sources and an examination of all the available historical material.

He states in his book that the man we know as King Arthur was the son of a fifth century king who ruled over the kingdom of Elmet in what is now east central England. His family castle would have stood on or near Hall Tower Hill in Barwick-in-Elmet, a suburb of Leeds where there is a mound and ditch that was once home to an Iron Age fort

Grant relied on many sources but especially Gildas, the sixth century monk who wrote a polemic commonly known as The Ruin of Britain.

“Gildas did not divide his excoriation of British kings into chapters,” says Grant, “but although later editors, trying to make it more readable, thought they were being helpful by inserting subheadings, what they actually did was to impose their own misunderstanding.

“Disregarding the subheadings was the key to identifying [for the first time in 1000 years] that the ‘enemy’ of the 530s when Gildas wrote was NOT the Anglo-Saxons, but rather the Picts and the Scots – it was then far easier to understand other texts better.”

Grant identifies Arthur as Laennog, younger son of King Masgwid Gloff of Elmet whose name became Arthur over time as stories told as entertainments grew arms and legs.

In the late 590s and early 600s, Grant says his war leader won the area that later became the Earldom of Lennox around Loch Lomond for the Damnonii people who ruled Strathclyde. The winner of 12 battles, he is commemorated in the name of a mountain near Loch Lomond we call the Cobbler but whose real name is Ben Arthur.

Grant told The National: “I believe the Damnonnii and the Gododdin asked for help and the other Britons said if you want our help it’s Arthur who’ll be our man in charge.

“We know that this man became viceroy of the kingdom of Camelot situated around West Lothian and Falkirk and that his sister was Thenew, mother of St Kentigern.”

Carroll on the other hand relies on the fact that his contender was known as Arturius from almost the start, as is so named in the Life of St Columba written by Adomnan, Abbot of Iona.

“He is named as Arturius by Adomnan,” said Carroll, “and there is so much else that fits the stories of Arthur. Arturius was the son of a sixth century Scottish king called Aiden. There is no doubt in my mind that Arturius is the real King Arthur.

“Both were active in the sixth century, both died in battles against the Picts, both were Christian, both fought alongside Urien and other British kings and both had a sister called Morgan – a name unheard of in sixth and seventh century records.”