Military

he early Roman army (c. 500 BC) was, like those of other contemporary city-states influenced by Greek civilization, a citizen militia that practiced hoplite tactics. It was small (the population of free men of military age was then about 9,000) and organized in five classes (in parallel to the comitia centuriata, the body of citizens organized politically), with three providing hoplites and two providing light infantry. The early Roman army was tactically limited and its stance during this period was essentially defensive.[91]
By the 3rd century BC, the Romans abandoned the hoplite formation in favor of a more flexible system in which smaller groups of 120 (or sometimes 60) men called maniples could maneuver more independently on the battlefield. Thirty maniples arranged in three lines with supporting troops constituted a legion, totaling between 4,000 and 5,000 men.[92]
The early Republican legion consisted of five sections, each of which was equipped differently and had different places in formation: the three lines of manipular heavy infantry (hastati, principes and triarii), a force of light infantry (velites), and the cavalry (equites). With the new organization came a new orientation toward the offensive and a much more aggressive posture toward adjoining city-states.[92]
At nominal full strength, an early Republican legion included 4,000 to 5,000 men: 3,600 to 4,800 heavy infantry, several hundred light infantry, and several hundred cavalrymen.[93] Legions were often significantly understrength from recruitment failures or following periods of active service due to accidents, battle casualties, disease and desertion. During the Civil War, Pompey's legions in the east were at full strength because they were recently recruited, while Caesar's legions were often well below nominal strength after long active service in Gaul. This pattern also held true for auxiliary forces.[94]
Until the late Republican period, the typical legionary was a property-owning citizen farmer from a rural area (an adsiduus) who served for particular (often annual) campaigns,[95] and who supplied his own equipment and, in the case of equites, his own mount. Harris suggests that down to 200 BC, the average rural farmer (who survived) might participate in six or seven campaigns. Freedmen and slaves (wherever resident) and urban citizens did not serve except in rare emergencies.[96]

After 200 BC, economic conditions in rural areas deteriorated as manpower needs increased, so that the property qualifications for service were gradually reduced. Beginning with Gaius Marius in 107 BC, citizens without property and some urban-dwelling citizens (proletarii) were enlisted and provided with equipment, although most legionaries continued to come from rural areas. Terms of service became continuous and long—up to twenty years if emergencies required it although Brunt argues that six- or seven-year terms were more typical.[97]