... the statement in the Annales is merely an amplified version of that given by Nennius.  The chief importance, in fine, of this first entry consists,... in showing that at least as early as the tenth century Arthur had become for the Welsh an heroic legendary figure...
    ... it shows, already developed, the tradition of a battle at "Camlann" in which Arthur was killed, and together with him a warrior named Medraut.  But special notice should be taken that this is absolutely all the information which it gives.  Whatever the author may have had in mind, he does not say that Medraut was Arthur's nephew, or a traitor, or even that he fought on the opposite side. (Studies and Notes in Philology and Literature: the Arthurian Material in the Chronicles, Fletcher, v.10, 1906)