Chrétien de Troyes states in his story of the Grail that he took the story from a small book provided by his benefactor, Philip of Flanders.
   One of the theories put forth is that Phillip acquired the book via his close trading links with the Cistercians of Melrose Abbey. They had huge numbers of sheep and so much land that the other locals complained of their dominance. They traded wool to Flanders as the damp Flemish air was perfect for working the wool. They traded directly with Phillip and even ended up exempting him from taxes as he became a protector of the Abbey. There were also close links between the Cistercians of Melrose and the Bishops of Glasgow based at St Mungo's cathedral (St Kentigern). The research that King David I had done on Kentigern's life for the foundation of the diocese led to the 'vita kentigerna' with the Lailoken (Scottish Myrddin) episodes.
   Another possible source for Philip's small book is that it may have arrived with Phillip's returning troops from Cumbria along with knowledge of contemporary Galloway and such northern places as given in Norman, such as 'Daneborg' 'Cardueil' & 'Cotouatre'. King David I of Scotland had been captivated enough by Arthurian matters to personally fly the dragon standard and his capital was Cumbrian Carlisle. It was there in 1149 that he knighted his grandnephew the young Henry Plantagenet on a Whit Sunday. Ailred who tells us of the barbarity of the Gallowegians spent his early life at the Scottish court before going to Rievaulx. It would have been there that he himself heard the tales that he would later 'remember' that had brought him to tears and '...commonly told of I know not what Arthur'. It has also been pointed out that Phillip of Flanders was in alliance with King William of Scotland who intended to reclaim Carlisle and his lost lands in Cumbria and had Flemish troops fighting in this area in 1174. In that same year, the sons of Fergus of Galloway, Uchtred and Gilbert, revolted and slew 'all the strangers, English and French whom they could lay hands on. All the strongholds and castles which the king of Scotland had built, they besieged, captured and destroyed, and all whom they seized within they slew.' At its bloody height, Gilbert's son then slew Uchtred and Gilbert and gave allegiance to King Henry.