The CSA would never ever have their capitol in some Northern Yankee city like New York or Philadelphia, or Boston or even Columbus Ohio. I'd say the best bet would be Richmond VA, or even New Orleans as a sleeper pick.
Richmond because it was the Confederate Capitol during the war, because nearly all the Generals and members of the upper class were Virginians. I mean heck, the army that Gen Lee was in charge of was called "The Army of Northern Virginia". I really cant see them going up to Boston or Philly when they had a perfectly good Capitol on Southern ground. Everyone needs to remember how divided everyone was back then. Calling oneself an "American" was really a novelty. Mostly people identified themselves as Virginians, Pennsylvanians, and so on, so the very idea of a Confederate government being established above the Mason Dixon line is crazy to me.
Richmond because it was the Confederate Capitol during the war, because nearly all the Generals and members of the upper class were Virginians. I mean heck, the army that Gen Lee was in charge of was called "The Army of Northern Virginia". I really cant see them going up to Boston or Philly when they had a perfectly good Capitol on Southern ground. Everyone needs to remember how divided everyone was back then. Calling oneself an "American" was really a novelty. Mostly people identified themselves as Virginians, Pennsylvanians, and so on, so the very idea of a Confederate government being established above the Mason Dixon line is crazy to me.