Yes, pretty well all related and intertwined, I think--Jungian archetypes and synchronicity at work, for sure. And too, we live in a very finite world--only so many twists and turns to be incorporated into myths and legends (and their incarnations in religions), and literature in general. But specifically, I would say that Arthurian and Norse are not the same...not in outward appearance, detail, and effect, anyway. I waded through the entire Malory as a graduate student, but it was tough keeping up my interest. On the other hand, I have always been all-consumingly fascinated by Wagner's version of Norse/Teutonic mythology in his Der Ring des Nibelungen. 'Course it didn't help that Malory is in an archaic English nor hurt that Wagner enhances the story with his ravishingly incomparable music! Call me a purist (or a clod), but I don't particularly cotton to what I consider Tolkien's mishmash of, apparently, all world mythologies. The Gol(l?)um's name, for instance, is certainly derived from the Jewish Golem, though I'm too little familiar with Tolkien's actual works themselves (Bad critic! Bad critic! For shame! For shame!) to know whether their actions and functions are similar. [I think Avalon is the never-never land to which Arthur's body sails, and Yggdrasil the Norsemen's World Ash Tree...? Must go back and look.....] --Wups! I really got carried away--apologies...!
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I don't know about Arthur, but I'm pretty sure that Cleopatra drove a Chevrolet--so I'll choose:
GM
World Titan or Bankrupt Octopus ?