Also remember crusades are a cheap way to get coin. Recruiting is dirt cheap, and you can just sack the settlement (usually a capital with lots and lots of coin) and destroy all the buildings....then just move the army and leave rebels take it over. This army you are now paying for, but the initial recruiting costs were so low it doesn't matter...now just go on a rampage against your enemies. Destroyed Portugal this way and used the money to improve my own settlements which in the long run earns me more money. Also I find that other sides are less likely to go on a crusade against a catholic side, which means you are always first there. It certainly is good to be friends with the pope .