Ben of Majestic Knight did this excellent page where MM realizes that Knight might be more than just an antiquarian, or somewhat deluded. The battle hymn, the details about who was Pope during the battle of Mt. Badon and Camlann (two historical battles where the dux bellorum---warchief-- Arthur fought in real life), the famines in the two winters before the battle of Camlann (caused by a volcanic eruption that lowered much of Europe's temperatures)...all real. (Those two battles were pivotal to Sixth Century England. The Butterfly Effect can be cited here. If the two universes had a different history in the sixth century, likely their two timelines would be MUCH different--their two USAs would not be so similar.)
I think Ben did an excellent job---the colors are muted, and make a nice compromise between his usual black and white style and the brighter colors the rest of us use--and show MM's slowly coming to believe the Knight is who he believes he is.