ABSTRACT

Rome’s civil wars split the state into factions, and the army with it. Since there were no ethnic, ideological or social differences between the rival sides, it was inevitable—even more than in any other civil war—that the organisation, tactical doctrine and equipment of their armies was virtually identical. The main strength of the Roman army lay in the legions, units with a paper strength of about 5,000. In theory the legions were recruited only from Roman citizens, but during the civil wars many non-citizens were enlisted to bolster numbers. In his Commentaries, Caesar frequently emphasised the heterogeneous nature of the enemy armies, but he had himself formed an entire legion, Legio V Alaudae, from Gauls, only later giving them the franchise as a reward for distinguished service. Given the dominance of the Roman military system, some allied kings had remodelled their armies after the Roman style. King Juba of Numidia included four legions in his large army, while Deiotarus of Galatia formed two which would later be amalgamated and formed into Legio XXII Deiotariana as a fully fledged part of the Roman army.