So I need something to make me think of the setting in a different way - something like Jeff's Wessex. He distanced his setting from real world England by using a fictitious map with the names changed. I kept trying to figure out how to do the same, but the only headway I ever made was by changing the Auvergne to Averoigne, but that comes with certain tonal implications and also the added baggage of trying to represent one of CAS's settings faithfully.
I hit a brick wall, but last night I remembered this:
click to embiggen
That is a map of what would have been the Known World to the Greeks and Romans. Note that Asia is at the top and Jerusalem is roughly in the center as in a Mappa Mundi. This map contains the parts of the world I'm likely to run a campaign in (Western Europe and the Mediterranean) but is still fantastic enough that I can distance myself from worries about accuracy.
Here is a list of historical games I could see myself running at some point:
Rome c. 150 - 100 BCE
PCs are ex-soldiers or otherwise homeless people who seek to make their fortune in the Eternal City.
Rome c. 400 CE
PCs are a comitatus of Germanic raiders, Roman mercenaries, or whatever else they want to be trampling the Roman Empire under their sandaled feet.
Britain c. 450
PCs are the leaders in a Briton community facing an invasion by some slightly inhuman Anglo-Saxons, weird forest gods, and other British groups.
Ireland c. 850
PCs as Viking settlers in Ireland. I actually ran this one session or two in college, but the group ended up not being able to meet due to schedule stuff.
Southern France c. 1050
This is a Cthulhu Dark Ages idea I've been kicking around. PCs work for the bishop of a cathedral town investigating reports of miracles, monsters, and banditry.
Byzantium c. 1050
PCs as mercenaries - Latin, Viking, or otherwise - in Constantinople or a fictitious Byzantine city. Become emperor or get blinded trying!
Southern France c. 1221
See the above link to the Fistful of Denars Post.
England c. 1215
Can you say "Robin Hood?" This one is a bit more half-formed than some of the others, but it'd be pretty awesome to run a game about medieval outlaws.
The Holy Roman Empire c. 1390
Robbers, cut-throats, and adventurers in post-plague Germany. Think Darklands but with maybe a tinsy-winsy bit more fantasy elements.
Looking at that list, I see that I'll need to clean up Northern Europe a bit to make room for Scandinavia so that those vikings can come from somewhere. The general rule will be that if you're in Western or Northern Europe or the Mediterranean it'd look more or less the same but with monsters and magicians. The further afield you go, the more it gets like something John Mandeville would write about.
I'd set up each of these campaigns in the following way:
1) History before the start date of the campaign went more or less as it did in the real world - excluding those areas that are cut off on the map.
2) The PCs' actions will constitute the basis of a new, alternate history.
3) Later campaigns set after the events of one that's already been played will make references to events in that campaign. So if you make your guy Roman Emperor, he'll show up on a list of emperors you find in the HRE game and you'll probably find coins with his face on him.
4) All of them will have way more monsters and dungeons on them than historical Europe did (i.e. they will have some). This one probably goes without saying, but my wife was quite worried there would be no dungeons when I pitched this to her. She loves dungeons.
One final note: I'm not getting rid of the Dark Country or anything. This was more of mental exercise to see how I would run a setting where Romans were Romans and Vikings were Vikings without being filled with crippling doubt.