You will also need lots of prestige in order to create the Roman Empire. In order to make this title you need to capture several duchies in Italy including Latium, Ferrara, Genoa and Venezia, the Balkans, Asia Minor, Syria (Antioch), Coast of Egypt (Alexandria) and North Africa (Tunisia). The Byzantine Empire and the Holy Roman Empire (if Byzantine conquered) are the only empires that can create this title. The Roman Empire is part of the Legacy of Rome DLC.
