Ancient History & Civilisation

The Roman Army

Like the Greek city states Rome had originally possessed a hoplite army, composed of citizens wealthy enough to equip themselves with the panoply of a heavy infantryman. Most hoplites were farmers and could afford to spend only a few weeks on campaign before they needed to return to their fields. As a result a conflict between the hoplite armies of two city states was of short duration, usually decided by a single clash between the rival phalanxes. The principle of a citizen militia was retained at Rome, long after other states had come to rely on professional soldiers. However, the Romans modified the system to cope with demands of wars which were being fought further and further away from the city, and the intimate link between hoplite warfare and the agricultural year was broken. From the beginning of the fourth century the Roman State paid its soldiers for the duration of their service. The wage was not high and certainly did not make the army a career, but it supported the soldier during his service. Men now served in the army until they were discharged, usually at the end of a campaign which might last more than one year. Some effort was made to distribute the burden of military service evenly throughout the population, since it was rare that more than a small minority of citizens were required for the army in a single year. Legislation required a man to serve for no more than sixteen campaigns and it was unlikely that many men reached this maximum before the Punic Wars. Effectively the Roman army had changed from a citizen militia into something resembling a conscript army similar to those which flourished in Europe after the French Revolution. The State could call upon citizens to serve in the army and for the duration of their service it provided them with food and pay, but also required them to be subject to military law and a harsh system of discipline. The willingness of Roman citizens to submit to these conditions allowed the Romans to develop an army that was larger, better trained and more complex than the citizen armies of any other city state.22

Our most detailed picture of the Roman army is provided by Polybius, but it is difficult to know whether all the practices he describes were followed throughout the period of the Punic Wars. His description of the army appears to be set in the Second Punic War, although it has sometimes been argued that it refers to the mid second century. We do not know whether or not the armies fielded in the First Punic War were significantly different to this in structure and tactics, but the admittedly brief descriptions of the battles in this conflict do not suggest this.23

Originally the word legio (legion) had simply meant army or levy and referred to the entire force raised by the Roman people in one year. However, as the number of citizens regularly enrolled for military service increased, the legion became the most important subdivision of the army. By the third century the legion consisted of five elements. Its main strength consisted of the three lines of heavy infantry. All of these men had the same basic property qualification and they were divided according to age and experience. The youngest men formed the front line and were known as the hastati. In the second line were men in their late twenties to early thirties, considered by the Romans to be the prime of life, and were called the principes. The third, rear line of heavy infantry were thetriarii, consisting of the oldest and most experienced soldiers.

Each of the three lines of heavy infantry was divided into ten maniples. Maniples of the hastati and principes consisted of about 120 men, although in times of crisis when larger legions were raised this might be increased to as many as 160. The maniples of thetriarii always consisted of sixty men. All maniples were divided into two centuries each commanded by a centurion, but these did not fight independently and the maniple was the basic tactical unit of the legion. If both centurions were present then the commander of the right-hand century was senior and led the maniple. Centurions were chosen usually from experienced and proven soldiers, steady rather than especially bold men, but had to be literate, since even at this time the army had developed a considerable bureaucracy. The second in command to the centurion was the optio who probably stood at the rear of the formation and helped to keep the ranks dressed. Other officers in the maniple were the signifer who carried the standard, and the tesserarius who supervised the posting of sentries at night and distributed the day's password on a clay tessera. Polybius twice mentions in his narrative a legionary cohort, telling us that this is what the Romans call a unit of three maniples, although the Greek is slightly ambiguous. In the late Republic the cohort consisting of one maniple from each of the hastati, principes, and triarii replaced the maniple as the legion's basic tactical unit. It is probable that when other authors mention legionary cohorts during the Punic Wars they are guilty of anachronism. There is no indication that it was a permanent subdivision of the legion in the third century BC and most probably 'cohort' was simply the term used to describe any ad hoc formation larger than a maniple, although perhaps detachments of three maniples were particularly common.24

The defensive equipment was the same for all three lines. The most important item was the oval, semi-cylindrical body shield, conventionally known as the scutum, about 4 feet (1.2m) long and 2 feet 6 inches (76cm) at its widest point. It was constructed of up to three layers of plywood glued together and covered with calf-skin, a combination which made it both flexible and resilient. The top and bottom edges were protected by brass strips to defend against sword cuts, whilst the layers of wood were thicker around the centre. The shield was held by a horizontal hand grip behind the central boss, which was usually bronze or iron, but sometimes perhaps of wood. Judging from reconstructions based on a surviving first-century example found in Egypt, the Roman shield was very heavy, weighing around 22 lb (10 kg). During lulls in the fighting its weight could be rested on the ground, but during combat it was held rigidly in front of the legionary and offered good protection for his body down to his knees. In addition to his shield, a legionary wore a bronze helmet, bronze greaves and some form of body armour. Wealthier men sported a mail cuirass of linked iron rings which, although heavy, was flexible and offered good protection. Poorer legionaries made do with a circular or square pectoral, a bronze plate suspended by leather straps which covered only their chest. Unlike the Greek design made of flexible bronze which clipped onto the leg, Roman greaves were tied into place. In some cases a man wore only one greave, usually on the left leg which was held nearer to the enemy in the classic Roman fighting posture, as a man turned his left side towards the enemy, protecting as much of his body as possible behind his shield. The most common Roman helmets seem to have been the Montefortino and Etruco-Corinthian designs, both of which offered good protection to the top of the head. Both were topped by a tall crest, of two black and one purple feather according to Polybius. The crest made the soldier seem taller and more intimidating to an opponent.25

All legionaries were primarily swordsmen and it was most likely during or after the First Punic War that the Romans adopted what they called the 'Spanish sword', the short, cut-and-thrust gladius, which was to be their standard side arm until the third century AD. Probably copied from Spanish mercenaries in Carthaginian service, the gladius had a blade of around 20-24 inches (51-61 cm) ending in a long triangular point designed to puncture armour. Most examples reveal high quality workmanship and confirm that the sword was able to retain a wickedly sharp edge. The tri-arii retained the old hoplite thrusting spear, but both the hastati and principes were equipped with the pilum, the famous Roman heavy javelin. The origins of this weapon are as unclear as the date of its introduction, but it was certainly in use by the last quarter of the third century and there is no good reason to believe that it was not also in use in the First Punic War. Polybius tells us that each legionary carried two pila, one heavier than the other, although it has not proved possible to categorize the surviving examples so neatly. In each case a wooden shaft about 4 feet (1.2m) in length was attached to a narrow iron shank 24-30 inches (61-76 cm) long topped by a small pyramidal point. All the considerable weight of a thrownpilum was concentrated behind this point, giving it the momentum to punch through an enemy's shield and still allow the narrow head to go on and strike the target's body. Even if it did not wound an enemy the pilum was difficult to dislodge from a shield, often forcing an enemy to drop it and fight unprotected.26

Poorer citizens, and those not yet considered old enough to join the hastati, served as light infantrymen or velites. Although it has sometimes been suggested that the velites were only introduced in 211 and replaced the less well armed and efficient rorarii, this has been based on a dubious interpretation of a single passage in Livy. It is more likely that the two terms were synonymous, although perhaps velites came into common usage at a later period. Polybius describes the velites as armed with a gladius and a bundle of light javelins. They were protected by a circular shield 3 feet (40 cm) in diameter and many wore helmets which they covered with pieces of animal skin - often wolfskin , to make themselves more conspicuous to their own officers. It is unclear how the veliteswere organized as they certainly did not form maniples of their own. Probably they were attached, at least for administrative purposes, to the heavy infantry maniples. In battle they fought as skirmishers in open order, supporting either the three infantry lines or the cavalry. There were normally 1,200 velites to support the 3,000 heavy infantry of the legion, but at times of crisis their numbers might be increased.27

Like the triarii the numbers of the cavalry component of a legion never changed. There were always 300 horsemen divided into ten turmae of thirty, each led by three decurions. The cavalry was recruited from the wealthiest citizens in the State, including the top eighteen centuries of the voting assembly, the Comitia Centuriata who were rated equo publico, obliging the State to provide them with the cost of a remount should their horse be killed on active service. Cato was later to boast that his grandfather had had five horses killed under him in battle and replaced by the State. This class included the sons of senators and it was as cavalrymen that many served out some of the ten campaigns which were needed to make a man eligible for political office. Cavalry service offered a chance for a man to make a name for himself which would aid a subsequent career. As a result Roman cavalry were normally brave and inclined to indulge in displays of bravado and fight single combats. Their chief tactic was the headlong charge in battle, but they showed little skill as scouts during a campaign. Annoyingly Polybius mentions the equipment of the Roman cavalry before they adopted Greek-style equipment, but does not bother to describe the latter in detail, assuming that his audience would already be familiar with it. However, Roman horsemen seem to have carried a round shield, worn a bronze helmet and mail or scale cuirass, and been armed with a spear and sword, possibly a longer weapon than the gladius. It is probable that they already employed the four-horned saddle which gave later Roman horsemen a firm seat and meant that they were not hindered by the absence of stirrups, perhaps having copied the saddle from the Gauls who may have invented it.28

Each legion was commanded by six elected military tribunes, who were often young aspiring politicians but sometimes included experienced former magistrates. Pairs of tribunes exercised overall command in turn. When a legion took the field it was normally supported by an ala of allies which fielded about the same number of infantry and around 900 cavalry. As far as we can tell their equipment and tactics were essentially the same as those of the legion, but it must be confessed that our sources rarely provide much detail concerning allied troops. The individual Latin colonies contributed a cohort of infantry and a turma of cavalry. It is not clear whether cohorts were of a standard size, and we hear of units varying in strength from around 400 to 600 men. The pick of the allied infantry were formed into the cohorts of extraordinarii who camped near the general's tent and were at his immediate disposal. These troops headed the column during an advance and brought up the rear during a retreat. The ala was commanded by three prefects of the allies (praefecti sociorum), who were Roman citizens. It is immediately noticeable that no unit of the Roman army had a single commander. There were six tribunes to a legion, three prefects to an ala, two centurions to a maniple and three decurions to a turmaof cavalry. Only in the case of centurions are we told that one man in each maniple was senior. In every other case the Romans seem to have extended to the army their deep-seated dislike of entrusting sole political power to one man and preference for colleges of magistrates. To modern eyes the system seems flawed, and it would eventually be abandoned by the later professional Roman army, but it proved adequate for the relatively simple tactics employed by the legions in this period.

The very high number of officers certainly made it easier to control a Roman army. Centurions were chosen from the bravest soldiers, although Polybius emphasizes that it was normal to promote the men who were gifted leaders rather than individual fighters. A centurion was supposed to stay with his men, whom he led from the front and by personal example. Stubbornness and the refusal to give any ground were considered to be amongst their greatest virtues. In general the Roman army also placed great emphasis on individual bravery, having a complex system of military decorations and rewards. A soldier who saved the life of a fellow citizen received highest decoration of all, the corona civica, a laurel crown which was worn at every public festival in Rome and commanded great respect. Roman commanders held formal parades after a battle or at the end of a campaign, when conspicuous gallantry was rewarded, the achievements of each man being read out and admired by the serried ranks of the army. The greatest rewards were reserved for acts of individual boldness, such as fighting a single combat when there had been no need to do so. Aggression was encouraged in all ranks of the Roman army. The army made it clear what standards of behaviour were expected from its men, and was as willing to punish as to reward. A unit which failed badly in combat and fled without putting up a fight could suffer decimation, one in ten of its members being beaten to death. The remainder as a symbolic humiliation were issued barley instead of wheat and pitched their tents outside the ramparts. We hear at one point of defeated legionaries who were ordered to eat their meals standing up instead of reclining in the usual Roman style. The standards of discipline to which Roman citizens were willing to submit themselves during their military service were extremely harsh and much like those of a professional army. Sentries discovered asleep, usually propped up on their long shields, suffered the death penalty, as did men who stole from their comrades, and practising homosexuals.29

The discipline of the Roman army in this period was often very tight, citizens losing most of the protection offered by the law to civilians. Even at this early date, Roman armies generated large amounts of bureaucracy and had a rigid daily routine. This was emphasized by the marching camp, the highly organized, neatly laid out structure built every night by an army on the march. Always built to recognizably the same pattern, a camp had four gateways and two main roads running at 90 degrees to each other and meeting in front of the main concentration of command tents. Everything was regulated, from the positioning of each unit's tents and baggage to the duties carried out by various contingents, so that for instance the triarii always provided guards for the horse lines. The responsibility of various officers to supervise the sentries and pickets around the camp and to transmit orders for the next day's march were all clearly allocated.

In most years the Roman Republic fielded four legions. Each consul was given an army of two legions and two alae. In battle the legions formed the centre of the line with one ala on either flank. For this reason the alae were often known as the Left and Rightala. Legions were usually numbered, one consul commanding the First and Third Legions, the other the Second and Fourth. It appears that all the legions in existence were renumbered every year so few of these units developed a lasting sense of esprit de corps or identity. It was rare before 264 for a praetor to be given a military command, but during the Punic Wars this was to become common. A Praetorian army usually consisted of only one legion and ala. Each year the consuls were first allocated the most important and largest scale operations, and then praetors were put in charge of smaller campaigns. Usually a Roman legion mustered 4,200 infantry and 300 cavalry on formation, but this was not a fixed size, rigidly imposed. According to the Senate's judgement of the strength of the opposition, the size of the legion could be increased to 5,000, 5,200, or even 6,000. This was done by enlarging the maniples of the hastati and principes and increasing the number of velites. This did not require any significant change in the legion's organization or tactical system. In exactly the same way the size of the ala could be increased, which may in part explain the variation in the recorded size of Latin cohorts. In times of extreme crisis, each consul might be given four instead of two legions.30

The Roman army of this period operated most efficiently at the level of the consular army of two legions and two alae. This force of at least 20,000 men was well balanced, perhaps ten per cent of the total consisting of cavalry, and had a clear command structure leading up to the unchallenged authority of the consul. It was sufficient for most tasks, but there was no clear mechanism for providing the command structure of an army composed of the forces of more than one consul. The temporary office of dictator, whose authority superseded that of all other magistrates, was exceedingly rare. When two consuls joined forces then each man held command on alternate days. The system was not ideal and was used by later authors to explain some of the early disasters of the Second Punic War. However, earlier in the third century both consuls had occasionally joined forces and seem to have operated without major problems. Both consular armies also participated in the victory at Telamon in 225; but in this case the actions of the two armies were not concerted but the result of a happy chance, since both consuls had been unaware of the other's presence before the battle. The system of shared command was not ideal, but it may have taken a commander of Hannibal's great ability to exploit the opportunities it offered to an opponent.31

It took time to form a Roman army and then train and drill it to a reasonable standard. Throughout their history, the Romans' concept of the ideal commander was always a man who carefully trained and prepared his army before risking them in battle. The longer legions and alae remained in service the more opportunity they had to drill and the more experience they gained, so that steadily their efficiency increased. The armies which served for much of the Second Punic War were eventually indistinguishable from professional soldiers. The weakness of the Roman system was that every time the legions were discharged and a new army raised, the whole process had to start again from scratch. Most levies of citizens included men with prior service, but although this aided the process of making an army battle-worthy it did not render it unnecessary. Such men would not have served together in the same units and under the same officers. There is a little evidence from the second century BC for a class of semi-professional junior officers and centurions who viewed the army as a career. It is unclear how numerous these were and we have no idea whether or not such men existed in the third century.32

Roman generals were amateurs in a modern sense, in that they received no formal training for command. The twelve-month political cycle ensured that very few ever enjoyed the long periods of command common with their Punic opponents. In the event, only Hamilcar Barca and Hannibal were to show themselves to be markedly more skilled than their Roman opponents. During the later stages of the First Punic War, the Roman electorate seems to have favoured re-electing experienced men, something that became even more common in the Second War, when the Senate also made extensive use of its power to prorogue the imperium of a magistrate for an additional year or years. In this way many able leaders were retained, some commanding the same army for years on end. However, as with success in elections, whether or not a man's command was extended sometimes had more to do with his political influence than his ability. The Roman system produced some incompetents who led their armies to disaster, but it also produced men of exceptional talent, most notably Scipio Africanus. The average Roman commander appears to have been at least as good as his average Punic counterpart. He was certainly likely to be far more aggressive and, whilst this carried the risk of rashness, it produced more spectacular victories. It used to be claimed that the Roman army won its victories in spite of the shortcomings of its amateur officers, whose inexperience was compensated for by the skill of more junior men, especially the centurions. Yet Roman commanders needed to make many important decisions before a battle, and were highly active during the fighting, paying attention to the small detail of the action. It was a style of command which demanded considerable skill. Although they received no formal training, we should not forget that most Roman senior officers did have extensive military experience before they achieved high rank. They were also the products of a class which valued military glory above all else and had clear ideas about how its members should face the danger of battle. A senator was expected to embody the characteristics implied by the Latin word virtus, which embraced not only physical courage, but also technical and tactical ability.33

The standard Roman battle formation was the triplex acies, based around the three lines of legionary heavy infantry. The maniples of the hastati deployed perhaps six to eight ranks deep, with an interval equivalent to the frontage of the unit between each maniple. The formation of the principes was the same, but the maniples were stationed behind the gaps in the line of hastati. In the same way the smaller maniples of triarii covered the gaps between the units of the second line. This created a checkerboard of maniples, like the quincunx or number five on a gaming dice. Polybius tells us that each Roman legionary occupied a frontage and depth of 6 feet (1.8 m), although a later source makes it more likely that the frontage was in fact only 3 feet (90 cm) and the depth 6-7 feet, (c. 2 m). The distance between the ranks was necessary to allow the legionaries to throw their pila. Assuming a frontage of a yard (90 cm) per man and a depth of six ranks for the unit, then a maniple of hastati or principes would have occupied a frontage of 20 yards (c. 18 m) and a depth of just over 12 yards (11m). The entire legion would have formed up on a front of around 400 yards (c. 365 m), allowing for the intervals between the maniples, and the infantry of a consular army occupied something like a mile, assuming, as seems probable, that the alae deployed in a similar formation. We have no direct evidence for the distance between the three lines, and the above calculations must remain to a great extent conjectural, but do provide a rough idea of scale.34

Our sources clearly state that the legion deployed for battle with wide intervals between the maniples in each line. The advantages of such an open formation for moving across country are obvious, since it allowed the sections of a line to flow around any obstacles without losing their order, in a way that would have been impossible for a solid formation. However, the vast majority of scholars have refused to believe that the legion would actually have fought with gaps in the line, since surely this would have allowed a charging enemy to stream through the intervals in the Roman line, surrounding and overwhelming each separate maniple. They have therefore proposed various schemes allowing the legion to alter its formation and create a solid, unbroken line before it made contact with the enemy. Connected with this problem is the question of how the three lines of the triplex acies interacted with each other. Clearly the Roman tactical system was based upon the principle that the lines ought to be able to support each other. Theprincipes and triarii were able to join the combat in some way, and it is claimed that they might even advance and replace the troops in the front line, but it is not easy to understand how this was achieved. The problem is particularly complex if it is accepted that when in contact with the enemy the maniples were packed together in a solid line. In fact, it is far more likely that they were not and that the gaps in the line remained during combat, but in order to understand the Roman tactical system we must first look at the nature of warfare and battle in this period.

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