It would have to be a revolution, not a civil war. And it'd be fairly unlikely without significant butterflying. That said, there are lots of places you could look to as starting points: the luddites, the Chartists, the Peterloo massacre, the Great Reform Act, Irish Home Rule, etc. That said, I doubt it'd be likely for there to be a revolution until after the Napoleonic Wars. Afterwards, it's entirely possible that Wellington could become the leader of a right win regime which might then be toppled by revolution.