The Pope is dead.

[chilling]

It seems the Sicilians have taken out the Pope in my current campaign. I'm taking advantage of his absence to claim a little more land from my Catholic brothers. Will I get a message when the Pope reappears or will the first I know of it be a warning about excommunication?

[Brutal DLX]

There will be a message telling you the pope in exile is leading a rebellion to re-establish his authority. It is just like a normal loyalist rebellion. If you are lucky, the Sicilians will put down that rebellion in the same turn and the pope will go into exile once more

You will get a warning about excommunication if you continue in your conquesting ways, but only for wars you start after he came back, not for the very bad things you did while he way away...