I set up a game with a bunch of mods I downloaded and here are the results:
Didnt work:
-Historical Eras - the 2 different start styles by these mods counteract each other

Did work:
-Ls Australia
-Ls civ set IX
-Agressive and expansive AI
-Argentina Civilization
-Capture+
-Civ names by policies
-Conquest for Unique Building
-Conquest for unique unit
-Cypriot Empire
-Faster plot expansion
-Historical Religons
-India Civ pack
-Info addict
-IGE
-More Luxuries
-More Pantheons
-Randomize City names
-The Buccaneers
-Wonder Race Lost
-Yet (not) another earth map pack
-43 Civs

Hope this helped =D

Does NOT work:
Community Balance Patch (conflicting tech changes etc)
Any other tech tree overhaul (Of course)

Does work:
"Longer eras - historic" mod works for me.
Increase City Radius
Settle new cities 5 hexes away
Advancing Works
3rd unique component
4th unique component (these two may have issues if there are mid-game changes in later versions of the mod)
Ocean Cities
Gibraltar, Reef, and Krakatoa Fixes
Less ice on maps
New Civs haven't had any obviosu issues.

Originally posted by amborgeson:

Does NOT work:
Community Balance Patch (conflicting tech changes etc)
Any other tech tree overhaul (Of course)

Does work:
"Longer eras - historic" mod works for me.
Increase City Radius
Settle new cities 5 hexes away
Advancing Works
3rd unique component
4th unique component (these two may have issues if there are mid-game changes in later versions of the mod)
Ocean Cities
Gibraltar, Reef, and Krakatoa Fixes
Less ice on maps
New Civs haven't had any obviosu issues.

Are you sure historic eras works? I know it doesn't crash your game for one thing but in historic eras you are supposed to start with 2 settlers, 2 warriors, and a scout. With having both mods on you only start with one settler, nothing else(How this Ultimate Eras sets the spawn start for troops).
-Sorry if i was a bit rude at all I just wanted to point that out =3

It seems to work regarding tech vs production (so historical length eras), and given that both mods edit the start, one of them has to win out, so I consider it compatible in that the mod's over influence on the game continues.

If you wanted to, I beleive you coudl edit the .info file for Historical era's to be 'dependant' upon Ultimate Eras, whic means Ultimate would make it's changes, then Historic woudl make its own changes after, which would give you more units that would be neyond your starting tech.

Originally posted by amborgeson:

It seems to work regarding tech vs production (so historical length eras), and given that both mods edit the start, one of them has to win out, so I consider it compatible in that the mod's over influence on the game continues.

If you wanted to, I beleive you coudl edit the .info file for Historical era's to be 'dependant' upon Ultimate Eras, whic means Ultimate would make it's changes, then Historic woudl make its own changes after, which would give you more units that would be neyond your starting tech.

Ok I was judging by if each component of the mod worked so we just had different ways of judging =3

Originally posted by amborgeson:

It seems to work regarding tech vs production (so historical length eras), and given that both mods edit the start, one of them has to win out, so I consider it compatible in that the mod's over influence on the game continues.

If you wanted to, I beleive you coudl edit the .info file for Historical era's to be 'dependant' upon Ultimate Eras, whic means Ultimate would make it's changes, then Historic woudl make its own changes after, which would give you more units that would be neyond your starting tech.

Also about the historical era start i wouldn't suggest it with the happiness debuff that ultimate eras adds =3

I dont exactly have a list of compatible mods right now as I had to remove the mod for a bit (I'm still trying to work out what works with my group of mods), but I am almost certain that Saga of Man is incompatible with this... I had particle physics and telecommunications in the Ancient era and everything past the Postclassical era (one of the Saga of Man eras) was blank. I'll try and get a list up this week of the compatible stuff I have.

I don't know if you're still updating this mod but there are 2 mods that are not compatible and I want to play this with them.

-Future worlds
-Enlightenment Era

Great mod tho!

So it seems that all of the Colonialist Legacies custom civs from TPangolin get Agriculture for free instead of the Social Structure tech like everyone else. They still technically work as far as I've tested (which admittedly isn't very far), but I found the problematic SQL code and created a fix for it here - https://steamcommunity.com/sharedfiles/filedetails/?id=1930349309

The only catch is that I don't know enough about the custom civs or UEM to say for sure that it's not going to have any ripple effects in the late game, or in games with other configurations than mine. At any rate, just thought I'd share it here in case anyone cares to test it out.

It doesn't work with civ 5 - crashes every few turns. Work on this to be at least possible to use.

Originally posted by Romooska:

I don't know if you're still updating this mod but there are 2 mods that are not compatible and I want to play this with them.

-Future worlds
-Enlightenment Era

Great mod tho!

Same I would like future worlds compatible

The New Buildings mod doesnt seem to work with it, it removes the buildings