What Did I Just Read?

When I opened the document to read this excerpt from Romance of Arthur, I honestly was not sure what I was reading. I couldn't tell if I was being introduced to the original texts about King Arthur, whether Wilhelm was trying to prove that Arthur was or was not a real figure, or if he was trying to critique the authors as the writings morphed from being more historical to fantasy. There were moments where things were more factual, especially given the very first sentences of the chapter. "The romantic legend of King Arthur and his knights of the Round Table seems more and more to have had some foundation in history."(p.1) Based on that sentence alone I am thinking that the document is going to talk about the historical basis that the legend has. Then things shift greatly a few pages later when other fanatical things are happening like his son's grave never being the same length whenever it's measured or Arthur taking out over 900 soldiers with one swing of his sword. I was bewildered to say the least. Not a bad article since it does have the original texts in it which is helpful, but some clarity on the author's point would have been nice.