Led by the fearsome Tetricus, Gallic Rome benefit the 'Romanisation' and 'Administrators' traits which grant a bonus to public order when Latin culture is present and -20% political action costs respectively.
Zenobia begins as the smallest Roman faction and will need to rely on her superior technology to keep up with Rome and Gallic Rome. They also benefit from 'Piety', which gives a -4 bonus to banditry for each cult building owned. Palymra, lead by the regent Queen Zenobia, receive the 'Enlightenment Ruler' trait, granting them a 20% boost to the research rate.
They also receive a major diplomatic penalty with other Roman factions as a result of the 'True Roman' trait. There are 3 major Roman factions available to play: Palmyra, Gallic Rome and Rome, who all receive the 'Defenders of Civilisation' trait, giving them a 15% morale buff to all units when fighting in allied territory. Learn how to play the Roman factions in the Empire Divided DLC for Total War: ROME II with this handy guide.