On using your King on attacks, once your empire begins to grow, it is probably a bad thing to use him, as the attack will isolate him from your other provinces, leading to a temporary drop in provincial loyalty. Use heirs instead, to groom them for their future role. And whatever you do, don't use the King to attack an island...
100% loyalty will prevent revolts inside a province. If there is a faction reemergence in nearby provinces, you need to have the loyalty up to 120% to avoid being sucked into it.
Spies will increase provincial loyalty by 40% + 20% per star. Only the highest valoured spy counts, so having multiple spies in a province is a bit of a waste.
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