I found a very interesting take on King Arthur and the Quest for Camelot by David F. Carroll. Below is his chapter on Sir Thomas Mallory. Any Arthurian enthusiasts or scholars should definitely check out David’s book. It is a worthwhile read.

SIR THOMAS MALLORY HIS WORK – LE MORTE D’ARTHUR OR THE DEATH OF ARTHUR This work was written more than 500 years ago, Sir Thomas Mallory did not invent any of the story of Arthur, but simply drew it from two existing sources, one British and one French. The British source can be traced ultimately to the writing of Geoffrey of Monmouth, because although Mallory was said to have used a 14th Century poem for the story of Arthur’s expedition to Rome, this was itself based on Geoffrey of Monmouth’s fanciful story contained within his ‘History of the Kings of Britain’. The French source Mallory drew on was vast and complex, and consisted mainly of a work known as the Vulgate Cycle. There is no need here to trace the various elements that made up his and complex, and consisted mainly of a work known as the Vulgate Cycle. There is no need here to trace the various elements that made up his French source, but suffice to say that the main body of his work was derived from this source. Mallory then was responsible for the fusion of the various ideas and elements that form the basis of what is known today as the Arthurian Legend. In his work we find some interesting clues which point us more to the North rather than the South of Britain as the ultimate source of the Arthurian Legends. For example, he often uses the word Liones. Liones was a word used in Old French and Breton to describe Lothian, which as everyone knows, is a region of what we now call Scotland. He sometimes used a different spelling and wrote ‘Lyonesse’ for Liones. Incredibly subsequent writers ignored the fact that Liones was in North Britain, and in fact a part of modern day Scotland, and instead attached the word Lyonesse to Cornwall, claiming it to be part of a submerged area off the coast of Cornwall, and of course the fact that it was supposedly submerged and no longer visible adding to its mystery as part of the Arthurian legends. We can be certain that the French writers who were the source of most of Sir Thomas Mallory’s work, were in fact referring to a real and tangible region of Scotland when they referred to ‘Liones”, and not some mythical, submerged region off the coast of Cornwall. Liones meant Lothian. Another interesting point worth noting is the story of Tristram. Tristram is the latinization of Drust, who was a Pictish King. There is no need to discuss the whole story of Tristram here, suffice it to explain that he is another character in the legend who again has been appropriated by the South, and Cornwall in particular. When in fact all the evidence of a real Tristram comes from the North, and again from Scotland. he is called Tristram de Lionnesse, which attaches him firmly to Scotland and the North. He is mentioned in the old Welsh Triads as Tristram (Drust) son or successor of Tallorch, and since Tallorch was a Pictish King and Tristram was indeed his successor, there can be no doubt as to his origin being in the North, as the Picts only lived in the North. Also, and perhaps most interestingly, the story of Tristram entered the Arthurian legends directly from France, and not from Welsh or English sources, which would surely suggest that they had arrived in France directly from their source of origin, that being Scotland and the North. Most importantly however, is the fact that the French writers of the Tristram story were writing of a real person from a region of Scotland, this being the case there is every reason to believe that their stories of Arthur were based also on a real flesh and blood character from the same region. Mallory’s work was then the basis of what we know today as the Arthurian Legend, and as we have stated, he drew his information from two sources, one French and one British. The British source was ultimately the writing of a 12th century cleric known to history as Geoffrey of Monmouth.

Carroll, David (2012-02-09). Arturius – A Quest For Camelot (Kindle Location 157). . Kindle Edition.