Anyone try to upset the Pope?

In my current game I tried very hard to keep him on-side, but he allied with the HRE (the ahistorical goon! :)) and then betrayed our alliance when war broke out!

My elderly heroic Doge received the Holy Lance from the general bearing it, and lead an army against Rome, displacing the unholy despot.

I've managed to reconcile with the Papacy (bribed them with the loot from Rome), and gave them Sardinia as a new home.

The Papacy still supports the HRE however, so I don't think this is the last I will have heard of the Pope...