Back when I ran 1st edition, I broke out my "Atlas of the Medieval World" and told my players it was the campaign book.
Of course, I'm open to players changing how things turn out, but I like weaving Mythic Europe elements in and out of actual history--explaining historical events in terms of the secret magical realities behind them.
In my current game, set in Transylvania, it's 1223, and the historical struggle between the Teutonic Knights and the Hungarian crown is about to come to a head. IRL, in 1223, King Andrew told the TKs to leave, but they dug in, receiving a papal charter giving them authority over the territory (including where the PCs live). In 1224, King Andrew tried to militarily expel the TKs from the Burzenland and failed; he came back and succeeded in 1224, destroying a number of their fortresses (some of which were rebuilt in later centuries--including the famous Bran Castle, today known as "Dracula's Castle" for purposes that have more to do with marketing than history).
The PCs have had some interesting interactions with the TKs. They were tasked with collecting Arcane Connections to the various fortresses and their commanders. At one point, they had to perform a covert mission to rescue a Redcap from a TK fortress. They also took it upon themselves to destroy a TK toll booth not far from their home.
When 1224 rolls around, the Hungarian king will attack, but the PCs will receive strict orders not to interfere; King Andrew will retreat (as he did historically). In 1225, House Tremere will decide to covertly intervene: the PCs will be told to take action. It's quite possible that the leaders of the Tribunal, who have been using those Arcane Connections the PCs collected to spy on the TKs, will make sure that the TK commanders are suddenly mentally incompetent. It might even happen that Dietrichstein (Bran Castle) mysteriously collapses ...
I realize that this sounds like I've simply predetermined the story and the players are just sitting back while I tell it--so I should mention that this is intertwined with a number of other adventures that are more character-driven.
Sort of, in all editions, and yes, in one edition.
All editions have had some variation of the Realm Interactions Table, and what Realm predominates in a place can depend on human actions. So, as the monotheistic faiths have conquered and settled more and more of the world, Divine/Dominion Auras cover more of it and get stronger. In every edition that aura has penalized all powers associated with realms other than the Divine, while strengthening powers associated with the Divine. So, since the central player characters are usually magi, who usually use the Magic Realm, the "magic is fading" trope is true from their perspective, even though the opposite is true if you take the perspective of a character who uses Divine powers.
Now, in 3rd edition, there was the oddball "Reason" realm, which itself penalized Magic, Divine, and Faerie powers (though it had no effect, positive or negative, on the Infernal), while having no supernatural powers associated with it. As "Reason" spread, then, it weakened most supernatural powers while not strengthening any, which is of course the "magic is fading" trope played almost straight. But "Reason" was entirely exclusive to 3rd edition, being introduced in that edition as part of the idea that Ars Magica was the backstory of the World of Darkness, and then deleted in 4th.
The core book explicitly states in p. 217 that this is up to you to decide, but that the 'dafault assumption' is that magic is steady. For what it's worth.
I would only add that in addition, many areas are supposed to be "mundane", with no Realm affiliation and no aura. And parrs of the lore, such as the dissolution of the great german-wide Forest Spirit into lots of mundane regions spattered with smaller supernatural forests, suggest that this is due to areas that were once Magical, but have been turned mundane. So in this sense "magic is fading" is true. But this appears to be general background and history, rather than an active ongoing process the game assumed the PCs will need to deal with.
My preferred metaplot is that magic once faded - but now the PCs get to reverse that. That everything was once Magic, but was usurped by the Faeries in the titanomachia and then they themselves were driven out by the Divine. And now that paganism has faded, the PCs get to release the titans from their imprionment, installing them once again as the great powers controlling the world. With the twist that this actually kinda sucks, as such a world is inimical to humanity.
'Fading' implies that something is decreasing, implying a change.
What you describe is interaction: Divine Dominates Magic, not an actual decrease of magic.
As mentioned elsewhere in the thread, 3rd edition had explicitly declining/fading magic. No other editions have had this per se, though we've always had the Divine Dominates Magic thing, dues to realm interactions.
You can do what you want in your own sagas, obviously.
So, as the monotheistic faiths have conquered and settled more and more of the world, Divine/Dominion Auras cover more of it and get stronger. In every edition that aura has penalized all powers associated with realms other than the Divine, while strengthening powers associated with the Divine.
That’s interesting. Sounds like the Divine power source is antithetical to the Magic power source, struggling against each other for dominion. That’s how it is in Chivalry & Sorcery. Organised religion and Magic don’t mix. And Acts of Faith can be detrimental to a wizard.
And parrs of the lore, such as the dissolution of the great german-wide Forest Spirit into lots of mundane regions spattered with smaller supernatural forests, suggest that this is due to areas that were once Magical, but have been turned mundane. So in this sense "magic is fading" is true.
Maybe all the forests humans cut down to make farmland had something to do with that. So as man becomes more industrialised and leaches off the natural world, magic will wane.
