Something I wrote to a dude in the discord for anyone who's wondering (all this info will be put together in a structured article eventually.)
"So, first off there's going to be the Russian Empire and the United States; however, within the United States there's going to be two cultures. At the beginning of the single player campaign, the 2nd culture (the south) will have no "kingdom", however it's "lords" (generals/leaders) will still be roaming around trying to make the "south rise again". This also means that if you recruit troops in the southern USA, they will be southern troops; they will have poorer equipment (single-load rifles for example instead of lever-action/bolt) but will cost less.
So in the campaign there's always going to be a random chance the south will rise again, lol. So players are going to be having to deal with Russia (if they're playing american) awhile dealing with a civil war
United States, Southern United States, Canada, Russia, Mexico, some Native American tribes, Alaskan Natives
Of course there's also going to be outlaws
and I might include mercenary troops from other countries, like Brazil for example, or Germany/France you get the idea."