Was king Arthur real or fake?

He was real but not all the stories are. He was the last Celtic King of Britain before the Angles and Saxons took over and after the Romans left. He was not the same as the Roman centurian. He had mounted troops (knights of the round table). As he was Celtic he would have had a Druid (Merlin). Apparently he was descended from Bran the Blessed and Joseph of Arimathea. The original story has no infidelity between Guinevere and Lancelot.