The Dark Albion setting is an historical setting, in many ways identical to our own world in the 15th century. I have made some significant changes to the setting: replacing Catholicism with the worship of the Unconquered Sun (as part of the overall 'law v. chaos' theme of the setting), changing the names of several countries, making some areas less advanced than they were historically at the time, removing the united Holy Roman Empire (not that it was ever all that united to begin with), and of course, having France be a kingdom taken over by evil-frog men.
In fact, a lot of things still ultimately minimize those differences: While the monotheist religion is the Unconquered Sun, you still see a structure and hierarchy that is virtually identical to the Catholic Church (with the exception of the Clerical Order, which has some similarities in structure to the Templars). The name changes and the absence of a HRE largely doesn't change much (except that it makes the Commonwealth seem a bit more powerful in its absence). And while the Frogmen are a pretty big change, their relatively recent rise still leads to a nearly-100-year-long war between them and Albion.
In some ways, the biggest change is the reality of magic. While magic in Dark Albion is more underpowered (at least, the spellcasting is; while magic items are much more rare), the world is one where spellcasters study their trade in Oxford or Cambridge, where Clerics perform miracles, where monsters and demons and the living dead haunt the lonely places on the fringes of civilization, and where everyone knows elves and dragons are real.
How could such a world not be drastically different from our own?
It would seem, from our perspective, that the reality of magic would change everything. But in point of fact, at least presented the way it is in Dark Albion, that's not necessarily so. To understand why, you have to understand the paradigm under which medieval and Renaissance Europe operated.
In our own real world, magicians did learn their trade in the great Universities of Europe. They didn't get titles of mages, but occultists like John Dee learned their art even as they studied the other natural arts and sciences (in John Dee's case, at Cambridge). They understood magic to be a part and parcel of advanced education. Of course, there were also hedge witches and wise women or men who used folkloric charms, potions, curses, blessings and cures that continued well into the 19th and even the early 20th century. No, not wiccans or anything like what modern neo-pagans do today exactly, but a tradition of folk-ways that were based on a combination of inherited superstitions and assumed rules. And both the high magicians and the low magicians did what they did because they were certain these things were true, and the people high-born and low-born believed them to have real power. That's why Queen Elizabeth I consulted John Dee to determine the most auspicious date for her coronation, and why countless medieval and renaissance courts hired alchemists or astrologers, and likewise engaged in espionage or sabotage of the hired wizards of rival courts. That's why common folk would take their sick child to a wise woman to be passed through a split tree-trunk to be healed, or buried cats in the walls of their house, or drew charms on their doors, or left out bowls of milk to gain the blessings of local spirits. They did these things because for them magic was a very real force.
They went on pilgrimages to be cured, and prayed to saints and visited holy men, and occasionally young women or old monks gained enormous influence (and sometimes became threats to local power) because they had visions and prophecies or the power to heal. In our own world, hardly anyone, even people who claim to be strongly religious, actually truly believe in this sort of spiritual power; you'd have to go to places in Africa to still see that kind of Christianity for the most part. But in 15th century Europe, people mostly didn't pay lip-service or pretend or struggle to be convinced of these things, they were assumptions as entirely and definitely real to them as the laws of gravity are to us.
Elves and demons and other such beings were certainly and definitely real to their paradigm. That's why Martin Luther fought with demons sent to assail him. John Dee spoke with angels and found proof of their power in his own experiences. And regular people encountered these creatures, or the effects of their power and their danger, as part of their lives; even if it was often something just out of view, the consequences of these entities were immediately and visibly apparent to them.
So why wouldn't 'real magic' change medieval history? Because in the medieval world, our medieval world, magic was already absolutely real.
Of course, there is a conceit in my work, in the effort to try to keep Albion's setting as close to historical England as I wanted it to be, of having all the changes made assume a minimal impact in the overall course of events. I'm certainly not the first world-builder (or real-world-imitator, if you will) to do that; fantasy-historical fiction has done it fairly frequently. I didn't want to create a truly alternate timeline, because I thought there would be more value in keeping the timeline in most respects linked to our own history. I certainly could have, if what I wanted was to create a really radically different world, to have made more changes. I expressly didn't want that, and wrote accordingly. Some GM using Dark Albion could want that, and could feel free (from the baseline I created) to move however farther afield they might like. Just like some other GM might prefer, if they like, to take away much more of the magic and the supernatural, or even all of it, and use Dark Albion as a strictly historical no-working-magic D&D campaign, if they prefer. But even then, in that world, magic would be 'real', it just wouldn't have confirmable and openly visible effects.
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