This A-Z, I’m looking at aspects of medieval history that might be relevant to writers, and to finish, I wanted to look at a what if scenario, to see how that kind of alternate history might work. Also because it gives me an interesting Z word. Zoroastrianism, for those who don’t know, is an ancient (and still continuing, obviously) Persian religion focused on a division of the universe into positive and evil aspects, each represented by divine beings (which is obviously a massive oversimplification, and apologies to any Zoroastrians out there). Is there a scenario in which it could ever have been the religion of Medieval Europe, instead of Christianity?
It’s not as far-fetched as you might think. Why was medieval Europe Christian? Partly because of the influence of the late Roman Empire, and partly because of missionary efforts at the back end of what people call the Dark Ages. When the Emperor Constantine won the Battle of the Milvian Bridge, he made Christianity the official religion of the Empire. If he had lost the battle, one of the Empire’s other religions might have gotten the gig. And one of the most popular cults in the later Roman Empire was a kind of offshoot of Zoroastrianism that was particularly popular with its military. Even in the Middle Ages, ideas that link to Zoroastrianism were around. The Cathars put down in one of the more brutal crusades against heresy believed in a kind of equal positioning between good and evil, with a figure for evil given almost equal billing as the only real solution to the theological problem of suffering. So it’s easy to see how things could have gone another way while remaining very similar.
Of course, this alternate history game is one that has been played in many forms by many writers. Mary Gentle does it brilliantly in Ash. Jacqueline Carey does it in large parts of her world building. It’s great fun as a writer to take something small but fundamental, twist it, and see where the world you’re working with ends up.