I'm playing as Poland at the beginning of CK2 without the Old gods expansion so 1066. A rebellion starts in Poland at the beginning of the game or 1 or 2 years after. What is the best way to successfully win the rebellion without screwing up vital battles. Or is there anyway of preventing the rebellion?
Immediately boost the opinion of the two dukes beneath you as much as possible, via gifts, appointing them to positions, etc. This will cause them to give you a greater percentage of levies, which should be enough to win you the war. That is the most direct method prior to the war. Since your tech is equal and you have a better general, this should be enough to ensure you win battles as long as you don't screw up and damage your morale or attack at a serious penalty.