So, I was reminded recently of the Russians hinting at intervening on the side of the Union during the US Civil War. From what I read, the Russians were stringing the US along so they could keep a large chunk of their fleet in NYC and Baltimore, thus keeping it in warm-water ports in case a war over Poland broke out in the winter.
I know that there was unrest in Russian Poland at the time, but I am not clear how likely a war breaking out over this would've been. I assume the UK would have opposed Russia, but I'm not really clear how the other powers would've lined up either. Anyone with more knowledge of the period have some thoughts on this, or on how much (if at all) a European war breaking out in, say, 1862 would have affected the course of the US Civil War?