Getting Crusaded (as the unexcommunicated Italians?)

[Orange]

Well, the title says it all I guess.
Playing Glorious Achievement for the first time, I decided to give the Italians a go, sticking to my provinces and historical sphere of influence, I tried to build up a trade network in the Med.Sea.
For this I decided I needed Sicily too, so after a short, mainly naval war (which was started by those Sicilian pirates) I had conquered Sicily destroyed their fleet and got excommunicated. This was not good, as I did not have that many forces, relying on trade and alliances. So I decided the Pope and his household desperately needed a day off, and told them I would take care of the matters at hand in Rome. Said and done, no more excommunication and after a while the Pope returned and everything was fine. (The first Pope had however cried out for a crusade against me...)
Than, about 10, 15 years later, my most loyal and veeeeery strong German allies invaded Milan. Without succes, as my mercenaries kicked them off some Milanese mountains and sent them home. And than, after the battle, a parchment saying: "The Germans have declared a new Crusade. It is marching towards YOUR lands!"

I might be missing something here. Is the call to arms by the first pope still valid? I just had a crusade ready, but I could not launch that one on the Germans. We were both good catholics, so what has triggered it?

Thanks in advance for your replies!

[Stu35]

When you are at war with the pope you are automatically excomunicated - this includes when he comes back - you may be defending, but you are at war with him, and the only way to get excomunicated is to kill him, or kick him off and keep him down (the easiest way is to leave NO troops in rome and the papal states - then he only comes back with a small army, then you can move your bigger army in and crush him).

Of course to simply end all wars with christians inside of 2 years helps as well.