Brythonic Breeding

Question: I've heard that Merlin, of Athurian Myth, may have been an imported Zeus in ancient Brittonic times. I'm also curious, if Merlin were like this, would he have the same purviews he possessed in the Greek pantheon in addition to having Magic/Prophecy, or would Fate have changed things far too much?

Looks like someone has been reading Professor John Rhys. This is totally an opinion, so feel free to disagree with it, but: that guy is fucking crazy.

Actually, I have nothing against Rhys, who was a distinguished old scholar in the late nineteenth century and who did a lot of good work in the field of Celtic languages and folktales, but his views on Zeus are unorthodox, to say the least. You will not find much literature that links Merlin to Zeus other than Rhys' - in fact, there's hardly any, because it's not a theory that is shared by much of even the fringe community when it comes to Arthurian myth. Merlin is an enigmatic figure and it's a very popular notion among historians and mythographers that he might have roots in some Celtic deity or myth, but Zeus is usually not one of the people anyone is thinking about when they say that.

The evidence Rhys draws upon to link the two figures is sketchy at best. Being a linguist, he draws his conclusions from language, most prominently that he believed that the Irish Mac Og (a byname of Aengus) was the same root name as the Welsh Myrddin (which of course becomes Merlin after Geoffrey of Monmouth gets hold of it). Since he also believed that Mac Og and Zeus were the same (largely because both "overthrow" their fathers, Zeus in the Titanomachy and Mac Og in tricking the Dagda into giving up his home), it followed that Myrddin/Merlin, being Mac Og, must also be Zeus, albeit in a much later descended form. As for story evidence, Merlin turns Uther into Ygraine's husband in order to allow him to have sex with her without getting caught, which is similar to the myth in which Zeus turns himself into Alcmene's husband for the same reason, and Merlin was trapped by Nimue in an oak tree, which happens to be the tree sacred to Zeus. He also points to similarities between Greek temples to Zeus and Stonehenge, and theorizes that Stonehenge itself might have been dedicated to the worship of Merlin/Zeus.

There's a lot going on there, and not very much that we're particularly sold on, especially the root theory that Aengus and Zeus are the same dude (because they're not... like, at all). It's certainly possible, even likely, that Merlin has a basis in ancient mythology somewhere, and it's even possible that that mythology is from the more recent Greco-Roman imports instead of the native Celtic myths, but we don't think it's very likely. They just don't have very much in common, and the idea has been largely discarded in the last century or so of Celtic studies.

We'd suspect that Merlin is more likely to be an echo of one of the Celtic gods, especially one associated with magic or wizardry; maybe Manannan mac Lir or the Dagda or even Cernunnos. But, if you're really sold on the idea of Zeus-as-Merlin and we're just raining all over your Storytelling parade right now, it wouldn't be too far-fetched to decide that maybe Merlin was an Avatar form of Zeus, in which he decided to visit the World and meddle in the affairs of the northern Europeans for some reason, or even a Scion of Zeus (after all, Merlin is said to be half human!) who happens to resemble his father in a few key ways. The Fate half of your question is difficult to answer because we really don't think there's any way Zeus was worshiped as Merlin-a-god at any point so Fate doesn't give a damn about his associateds, but he already has Prophecy and probably at least a little bit of Magic for some of the shapechanging shenanigans he perpetrates on himself and others, so it wouldn't be much of a change even if you do go that route.

If you're going to roll with the wacky Merlin theory, we can only imagine you must have a truly amazing plot seed in mind.