Is King Arthur of Camelot a real person or myth only?

This is a controversial question, but here is my personal opinion. King Arthur was a king of the Britons, a Celtic people, in the fifth and sixth centuries. In the Easter Annals,a document from the dark ages, he is mentioned twice: 516: Battle of Mt. Badon in which Arthur carried the cross of our lord Jesus Christ on his shoulders for three days and nights and the Britons were victorious 537: Strife of Camlan in which Arthur and Medraut fell. Those aren't the exact Wordings but fairly close. Badon was crucial point in Arthur's military career because it stopped the Saxons from coming further west for a few decades. It is assumed that Arthur died in Camlan, but it is not really known. Perhaps he survived and retired from public life. Especially since he lost the battle. This could be where the legend of the once and future king comes from. He left Britain to his sucessor, Constantine of Dumnonia. If you are seeking more information about this topic, I highly recommend reading King Arthur: The truth behind the legend by Rodney Castleden. It goes into far more depth than I have. What I have stated is not all the evidence. There is more, but I don't have the time and will to write it all down right now.