Yes, I hate the Pope, thanks to the many excommunications in the Medieval 2 Total War. You can restore Western Roman Empire as christian or hellenic pagan ruler! I advise you not to do this as a Catholic ruler, because this will provide a endless headache because of this bastard in a tiara from Rome. Also, to restore legion system, you need to have Roman culture, 20 martial and 15 learning. But to create a new legion, you must control its historically native province, like Latium for Legio I Italica. You can restore ancient legion system and form 11 legions! Each legion has up to 6 thousand legionnaires, so you can defeat both the Mongols and the Aztecs alone. But be sure, this will provoke a civil war. You can overthrow republic and proclaim an empire! For that, you need to have a loy of money and prestige, and Republic must have an Empire tier.
Pope, begone!) and be a christian or hellenic pagan. You can now restore Roman Republic as any merchant italian (or greek, like Amalfi) republic! For that, you need to control most of italian lands (and Rome, of cource.
