In contrast to the Jomsvikings, Rome pairs well with the Quantity military ideas, which should swell your ranks to the point that globally-based legions are barely a tax on your resources. But hey, restoring Rome in CK2 isn't easy, so being rewarded with all the tools to become an intercontinental superpower is probably appropriate. This seems more than a little overpowered, based on the other idea groups in the game. Their traditions grant +10% Discipline and +1 Yearly Legitimacy, while completing the track gives you an insane +33% Manpower. Imperium Sine Fine: Core Creation Cost -20% Imperial Bureaucracy: National Tax Modifier +10% Roman Architecture: Production Efficiency +20%

The Roman Legions: Land Forcelimit +15%, Infantry Combat Ability +10% If you managed to restore the Roman Empire as Byzantium using CK2's Legacy of Rome DLC, they will be imported into EU4 as an Empire with a unique idea group: