Operation Byzantine Breaker was a success. I managed to install upon the throne a Zoastrian Ruler, who then let me leave the alliance, and who lost a considerable amount of power after her passing. Which, first, kudos to her in the first place, since a for just one moment in time, Zoastrians were once more relevant in the world. I managed to grab all of the Sicilian territories I needed to form Sicily; despite only actually owning just a token amount of proper island Sicily.
The only problem now is the Kingdom of Italy... Which became the Kingdom of Asturias, which became the Empire of Hispania. Huzzah. They are now much stronger than before, as they have nearly all of the Iberian Peninsula's territory to back them up.
So. While I could feasibly take it on in a fight, chunking tiny bits away every once and a while, I've decided to once more bow before a larger power. Which is to say, that I'm going for the old Independence back stab. After garnering enough favors from the masses and other duchies and kingdoms in the realm, I'm going to call for a state-wide revolt. This will inevitably chunk the kingdom into more bite-sized morsels and soon, after so many struggles, I will finally have formed Italy.
Then I will invade the Pope. And it will be good.