II. Empire
In the years following Actium, Augustus set out to secure for himself a monopoly of military power and glory, establish a legal basis for his control of the legions and direction of foreign policy, and build an army that could undertake a programme of continuous warfare. This last task was a considerable one; apart from the initial hurdle of paying off the thousands of weary and near-mutinous soldiers who had survived the civil wars, it was complicated by the political necessity of curtailing or materially reducing conscription in Italy. The army Augustus bequeathed to his successors was a body of professionals, serving for twenty-five years at the modest pay of 225 denarii a year (raised to 300 by Domitian) and with the prospect of a discharge payment of 3,000 denarii or the equivalent in land. The bulk of the legions, which were stationed in the Northern provinces, were made up of recruits – some conscripts, some volunteers – from the more Romanized West. Local and regional recruitment, for legionaries as well as auxiliaries, became the norm only after our period. The level set by Augustus of 28 legions, or about 168,000 men (plus roughly as many auxiliaries, recruited from non-citizens), was not raised significantly by later emperors.