Whatever the truth about Camillus, some such reforms must at some time have been carried through, to convert the Servian sys tem into the army which was engaged for nearly three centuries (from 35o B.C.) in conquering Italy and the world. This army broke in succession the stout native soldiers of Italy and the moun taineers of Spain and overthrew the trained Macedonian phalanx. Once only did it fail—against Hannibal. (See PUNIC WARS.) But not even Hannibal could oust it from entrenchments, and not even his victories could permanently break its moral. Much of its strength lay in the same qualities which made the Puritan soldiers of Cromwell terrible—the excellent character of the common sol diers, the rigid discipline, the high training. Credit, too, must be given to the genius of Scipio Africanus and to the more common place capacities of many fairly able generals. But the organism itself deserves attention, and, as it chances, we know much about it, mainly from Polybius. Its elements were three : (A) The principal unit was the legion, generally a division of men-3,000 heavy infantry, 1,200 lighter-armed (velites), 30o horse—though sometimes including as many as 6,000 men. The heavy infantry were the backbone of the legion. They were levied from the whole body of Roman citizens who had some pri vate means and who had not already served 16 campaigns, and in effect formed a yeoman force. For battle they were divided into 1,200 hastati, 1,200 principes and 600 triarii: all had a large shield, metal helmet, leather cuirass, short Spanish thrusting and cutting sword, and in addition the hastati and principes each carried two short heavy throwing spears (pi/a), while the triarii had ordinary long spears. They were drawn up in three lines: (I) hastati, (2) principes, (3) triarii; the first two were divided into ten maniples each (of .120 men, when the legion only counted 4,500), the third into ten maniples of half the strength. According to the ordinary interpretation of our ancient authorities, the maniples were ar ranged in a chess-board fashion (quincunx), the idea being that the front row of maniples could retire through the intervals in the second row without disordering it, and the second row could simi larly advance. The procedure in fighting seems to have been simple : the front line discharged a volley of pila and rushed in with the short sword—a sequence much like the volley and bay onet charge of the 18th century—and if this failed, the second line went in turn through the same process; the third line of triarii, armed with spear instead of pi/um, formed a reserve. The velites, armed with javelins, came to be used as skirmishers. The cavalry seem to have been of little account—a natural result if, as we have reason to think, the horses were small and stirrups were not used. Scipio Africanus alone developed his cavalry into a decisive in strument.
The officers of the legion consisted of : (a) Six tribunes, in part elected by the comitia, in part appointed by the consuls, and hold ing command in rotation. They were either veteran officers, some times even ex-magistrates, or young noblemen beginning their career. (b) Sixty centurions, each commanding one century, or, rather, a pair commanding each maniple. They were chosen by the tribunes from among the veteran soldiers serving at the time and were arranged in a complicated hierarchy, by means of which a centurion might move upwards till he became Primus paus, senior centurion of the first maniple of triarii, the chief officer of that rank in the legion. (c) There were also standard-bearers and other under-officers, for whom reference must be made to specialist publications.
(B) Besides the legions, composed of citizens, the Roman army included contingents from the Italian "allies" (socii), sub jects of Rome. These contingents appear to have been large; in many armies we find as many socii as legionaries, but we are ig norant of details. The men were armed and drilled like the legion
aries, but they served not in legions but in cohorts, smaller units of 400-500 men, and their conventional positions seem to have been on the wings of the legions. They were principally infantry, but included also a fairly large proportion of cavalry.
(C) Besides legionaries and socii, the Roman army included non-Italian troops of special kinds, Balearic slingers, Numidian horsemen, Rhodians, Celtiberians and others : at Trasimene, for example (217 B.c.), the Roman army included 600 Cretan archers. The numbers of these auxilia varied ; probably they were not numerous till the later days of the Republic.
Composition and Size of Armies in the Second Stage.—Accord ing to the general practice, each of the two consuls, if he took the field alone, commanded an army of two legions with appropriate socii. If the two consuls combined their forces, commanding the joint force in rotation (as often occurred), the total would be— according to our authorities—four legions, each of 4,200 infantry, the same number of "allied" infantry (in all 33,60o infantry), 1,200 legionary cavalry and about 3,600 "allied" cavalry = 38,400 men. Such, for example, was the Roman army at Trebia (218 B.c.), where (says Polybius) there fought 16,000 legionaries and 20,000 allied infantry. The total number of men in the field could be increased ; we even hear of 23 legions serving at one time in the Second Punic War. Just before this war, in 225 B.C., the total man-power of Rome was reckoned at three-quarters of a million. of which about 65,000 were in the field and 55,000 were in a re serve at Rome; of the total, 325,00o were Roman citizens and (apparently a rough estimate) were allies. The battle or der in normal circumstances was simple. In the centre stood the legionary infantry : on each side of that was the allied infantry : on the wings the cavalry. But sometimes the legions were held in re serve and the brunt (and honour) of the fight was left to the allies. Frequently the attack was begun by one wing, as by Caesar at Pharsalus. At Ilipa in Spain Scipio surprised his enemy by a last hour variation of the accustomed order. Putting his Spanish auxiliaries in the centre, his Roman troops on the wings, he "re-fused" his centre and attacked with both wings.
Development from the Second Stage to the Third.—To wards the end of the Republic many changes began to work them selves out in the Roman army. If Camillus began the system of pay and long service, it was effectually developed by long foreign wars in Spain and in the East. Moreover, the growth of Rome as a wealthy state tended to wreck the old theory that every citizen was a soldier, and favoured a division of labour between, e.g., the merchant and the military, while the increasing complexity of war required a longer training and a more professional soldier. In consequence, the old restriction of legionary service to men with some sort of private property was abolished by Marius about 104 B.C. and the legionaries now became wholly proletariate and pro fessionals. By a second change, also connected with the name of Marius, the legion was reorganized as a body of 6,000 men in 6o centuries, divided into ten cohorts instead of (as hitherto) into 3o maniples ; the unit of tactical action thus became a body of 600 instead of i 20. This was probably an adaptation within the legion of the system of cohorts already in use for the contingents of the socii. Soon after, the extension of the Roman franchise to all Italians converted allies and subjects into citizens, and the socii into legionaries. A fourth change abolished the legionary cavalry and greatly increased the auxilia (C., p. 396).