Quote Originally Posted by ShellShock
Is there any way of stopping rebels appearing in the first place? What is the trigger for their appearance? Perhaps the level of happiness in my cities?
This is a mystery. I think the province not only has to be happy, but the higher the "law" level of that happiness is, the better. That's just a guess, though. You can see how much local "law" contributes to happiness by checking the full city display.

I think bandits pop up like mushrooms whatever you do, whether you can see them or not. Also, armies left standing when a faction is eliminated go rebet.