Ancient History & Civilisation

Soldiers and Warfare in Late Antiquity


By the 4th century soldiers served 20 years, apart from in some of the less prestigious units amongst the limitanei, where men were expected to serve for 24 years. Some men were volunteers, but conscription appears to have been far more common than in earlier periods. Under the Principate soldiers were not legally permitted to marry, but the army informally ignored the rule, let soldiers raise families and often recruited their sons born ‘in the camp’. Severus’ decision to remove this legal ban led eventually to legislation forcing all sons born to soldiers during or after service to enlist in the army, making soldiering an hereditary career. Conscripts were also levied from the Empire on an annual basis, each community being obliged to provide a set quota of men. The assessment appears to have been based on land ownership, and tended to fall especially heavily on rural communities. Certain categories of men, chiefly those employed in imperial service, were exempt from this obligation, whilst men following unsuitable professions, and, in all but the most exceptional circumstances, slaves were barred from military service. In some years the emperor chose not to raise this particular levy, so that it is difficult to know how frequent it was. It also appears to have been fairly common for governors to permit the communities to pay a conscription tax in money instead of recruits, a system which was clearly open to corruption. Some officials levied the tax, and then used a small proportion of it to find sufficient volunteers - often inevitably of low quality - to provide the original quota of recruits. Attempts were made to prevent such abuses, but a constant trend in Roman law was aimed at preventing those eligible for conscription from avoiding military service. Cases of self-mutilation to avoid military service - a common method was to cut off the thumbs - occur sporadically throughout Roman history, but this may have been more of a problem as conscription became widespread. Constantine passed a law obliging soldiers’ sons who disfigured themselves in this way to undertake civil service in their communities, but measures became harsher as time went on, with Valentinian ordering such men to be burnt alive in 386. By the end of the century a different approach was adopted, and in 381 Theodosius stated that mutilated recruits were still liable to conscription and that two such men would count as one normal conscript.

Desertion had long been a problem in the Roman army, probably inevitably given the long terms of service and often harsh conditions. References to deserters appear frequently in the sources for the later period, but it is difficult to say whether or not this had become more common.

Barbarization? Recruits from outside the Empire

Significant numbers of recruits were drawn from communities of barbarian tribes settled with imperial approval within the Empire. Often the treaty granting them land required them to supply a set number of recruits on a regular basis. These were known as laeti or gentiles, but did not usually serve in distinct units and were treated much like other conscripts. Many men from outside the Empire were also drawn into the Roman army. At the end of a conflict prisoners of war were often conscripted into the army, though usually they were posted some distance away from their place of origin. A defeated people might also provide a number of warriors as part of the peace settlement imposed by Rome. Some individuals also chose to travel to the Empire and volunteer.

The recruitment of barbarians appears to have been fairly routine, and in principle was nothing new, for the auxilia of the Principate had also included men from outside the directly governed provinces. Yet we have no reliable statistics to establish the scale of barbarian recruitment in Late Antiquity. In the past it has often been seen as a sign of a desperate shortage of recruits, and perhaps additionally of the low quality of many conscripts from the provinces. Steadily, the Roman army became barbarized, as more and more of its officers and men were drawn from the uncivilized peoples, and in particular the Germanic tribes. These men had little reason to feel political or cultural loyalty to Rome. The problem became worse with the growing use of foederati, units in which barbarians served under their own tribal leaders rather than Roman officers. The Roman army is supposed to have decayed until it was little more than a mass of mercenary warbands led by barbarian chieftains. This is sometimes held to have been a major factor in the collapse of the western Empire.

As early as ad 69, Tacitus had depicted an army from the Rhine provinces, both legionaries and auxiliaries, as uncouth barbarians, shocked by the splendour and size of Rome. Similar rhetorical exaggeration may well have influenced the few late sources which criticize the spread of barbarians within the army. In the main our sources for the period do not appear to have seen this as a problem. Barbarian recruits were in general as loyal and efficient as any others, even when fighting against their own people. Occasionally barbarian soldiers turned traitor, but so in this period did some Romans. By the late 4th century many senior officers were of barbarian descent, yet most of these men appear to have been culturally assimilated into the Roman military aristocracy. The belief that ‘barbarisation’ of the army contributed to the fall of Rome has now been largely discredited.

Soldiers and civilians

By the 4th century the real value of the soldier’s pay was very modest, and needed to be supplemented by many payments in kind, including clothing as well as rations and fodder for animals, plus occasional imperial donatives. Most clothing and equipment was issued by the state, and provided either through levies on the provinces or produced in the imperial factories listed in the Notitia Dignitatum. The comitatenses in general had no fixed camps and for much of the time were billeted on the civilian population of towns and cities within the provinces. This was exceedingly unpopular - as it had been on the rare occasions it was employed in earlier periods - and there were frequent complaints from civilians accusing soldiers of taking more than was their legal right and of using violence.

Constantine's Soldiers, ad 312

In Late Antiquity, Roman troops were engaged in civil wars almost as often as they fought foreign enemies. As his army marched on Rome to defeat his rival Maxentius, Constantine claimed to have seen a vision of the cross in the sky, and following a dream, publicly became a Christian. Whether this conversion was political or genuine - or perhaps a mixture of both - is hard to say. However, his subsequent overwhelming victory at the Milvian Bridge seems to have confirmed him in his beliefs. Before the battle he had ordered his men to paint the Christian symbol of the Greek letters Chi and Rho on their shields. In this scene we see a senior officer inspecting the results.

The Battle of Strasbourg

ad 357

A confederation of Alamannic tribes had temporarily united under the leadership of two kings, Chnodomar and his nephew Serapio, and launched a plundering invasion of the Roman provinces along the Rhine. Julian the Apostate, the Caesar in the west, marched to confront them and, under pressure from his enthusiastic troops, attacked the barbarians near Argentoratum.

The forces

1 The Romans: 13,000 men including several legions and units of auxilia palatina.

2 The Alamanni: according to our Roman sources 35,000 men.

The fighting

Before the battle began, Chnodomar and his chieftains dismounted to fight on foot, showing their warriors that they would share their fate. The Germans concealed some men in broken ground on their right, but the Romans were suspicious and held back their left wing. On the Roman right their cavalry, including a unit of cataphracts, were routed and fled behind the two lines of Roman infantry, where they were rallied by Julian. The Alamanni launched a heavy onslaught at the first Roman line. Led by a group of chieftains they smashed through the Roman centre, but were stopped by the Primani, a legion stationed in the second line. Gradually, as the Romans committed more and more of their second line, the Germans were driven back and eventually collapsed in rout.


1 Roman: 4 officers and 243 men killed.

2 Alamanni: our Roman sources claim that some

6,000 were killed. Chnodomar was captured.


The victory helped to deter other raids on this section of the Roman frontier fora while. However, this would only prove effective for as long as the tribes outside the Empire believed that the Romans were strong enough to mete out similar retribution to any new raid.

JULIAN (ad 322-63)

The son of Constantine the Great’s half brother, Julian survived the brutal Civil War that swiftly followed the formers death in 337, but spent most of his early life as a well-cared-for prisoner. In 355 he was appointed Caesar of the western provinces by the Augustus (or Senior Emperor) Constantius II. During the next few years he campaigned with some success along the Rhine frontier. In 360 Julian's troops proclaimed him Augustus in opposition to Constantius, but the latter died of natural causes in the next year. As ruler of the entire Empire, Julian attempted to reverse Constantine’s decision to establish Christianity as the main religion of the Roman world. For this reason he is known as Julian the Apostate. However, the cult of his own devising, based around worship of the sun god, failed to become established.

In 363 Julian massed a huge army of some 70,000 men for an invasion of Persia. Although he penetrated deep into the enemy’s heartland, he was unable to force them into a decisive battle and his troops began to run out of supplies. In a confused night skirmish Julian was struck by a javelin and mortally wounded. The subsequent retreat of the Roman army was disastrous and Julian’s successor granted considerable concessions to the Persians to gain peace.

(Above) A statue of Julian the Apostate, now in the Louvre Julian had no prior military experience before he was appointed Caesar and never developed the ability to understand his soldiers' moods.

In the 4th century the north wall at Housesteads underwent considerable repair and renovation. The old stone wall appears to have collapsed and was widened into an earth rampart - a timber structure replacing at least one of the towers. In many ways the defences in this period resembled the hillforts of pre-Roman Britain.

The limitanei in general lived in forts. Some earlier forts, notably Housesteads and Great Chesters on Hadrian’s Wall, have revealed traces of extensive alterations in the design of barrack blocks near the end of the 3rd century. A single range of paired contubernium rooms was replaced by a row of some half-dozen individual sheds, each with their own external walls and roofs and separated by narrow alleyways. At Housesteads the individual sheds vary in size from around 8-10 m (26-33 ft) by 3.6-5.15 m (12-17 ft). These are known as chalet-barracks. There were invariably fewer of these buildings than there were contubernium rooms in the earlier, communal barrack block. Most chalets seem to have had hearths. One interpretation was to see these as homes occupied by one or two soldiers and their families, providing an indication of the diminishing size of army units in the Late Empire. There is no direct evidence to support this, and the discovery of similar chalet-barracks from the early 3rd century, before the supposed reduction of unit strength occurred, makes it extremely dubious. More probably the different design was a simpler and lower-maintenance alternative to rebuilding ageing barrack blocks to the original design.

The new religion: Christianity and the Roman army

Roman soldiers frequently acted as the agents of the state in the persecution of the early church. However, it is important to remember that in the 1st and 2nd centuries the suppression of the Christian cult was sporadic and not directed by central authority. Roman emperors did not in the main view the new religion as a serious problem, and most persecutions were prompted by periodic outbursts of hostility and suspicion in the local communities. This changed in 251, when Decius ordered an Empire-wide suppression of the cult. Other emperors, notably Diocletian, ordered similarly broad persecutions, but by this time the religion was too well established to be eradicated.

The attitude of early Christians to military service varied. The Book of Acts records the conversion of Cornelius, a centurion of a Cohors Italica, by St Peter. There is also a little evidence for Christians serving as soldiers, even within the praetorian guard by the 3rd century. However as late as 295, when summoned for military service as part of the annual levy, one Maximilianus could declare, ‘I cannot serve in the army; I cannot do evil; I am a Christian.’ His refusal subsequently led to his martyrdom.

In 312 Constantine destroyed the army of his rival Maxentius at the battle of the Milvian Bridge outside Rome. He claimed to have received a vision of the cross, and as a result had ordered his men to paint the symbol of Christ, the Greek letters chi-rho, on their shields. The next year Constantine and the Eastern Emperor, Licinius, proclaimed freedom of worship for Christians throughout the Empire. Throughout his reign Constantine actively, but not exclusively, promoted the new religion, although it was not until near the end of his life that he was baptized. The impact of the adoption of Christianity on the Roman army was in many ways slight, the ceremonies of the new religion replacing those of the old in army ritual and ceremony. By the mid- 5th century each unit in the eastern army had a chaplain, and these may have been introduced both there and in the west much earlier. The new faith did not significantly change Roman methods of war-making.

(Above) A medallion celebrating Constantins’ recovery of Britain from the rule of a usurper in 297. Constantius would later campaign extensively in northern Britain and died at York, where he was succeeded by his son, Constantine the Great.

Warfare in Late Antiquity

The problems faced by the later Roman army varied from frontier to frontier. In the east the Sassanid Persians, who had supplanted the Parthians in the early 3rd century, were large and powerful neighbours. On a few occasions Sassanid armies drove deep into Rome’s eastern provinces, at times even threatening Antioch. More often the Romans invaded Persia, the expeditions following much the same route down the Euphrates as had those of earlier emperors, such as Trajan, Lucius Verus and Septimius Severus. Neither side was ever able to turn temporary successes into permanent occupation. In the main the Romans and Persians concentrated their efforts on controlling the regions bordering their Empires. Pitched battles were rare, and raiding the most common military activity. This was often carried out by allies drawn from the local, nomadic peoples. Strongholds assumed a critical importance in these campaigns, since these provided bases from which raiders or interception forces could operate. Only the side which controlled these fortified towns could hope to dominate the surrounding area. Besieging such a stronghold took a great deal of time and effort, and ran the real risk of failure, which would seriously diminish a leader’s prestige. At times, the attackers’ skill and determination proved inadequate, but more sieges were ended when a field army came to the defenders’ relief. A good proportion of the battles which were fought occurred in these circumstances.

On other frontiers, the problem posed by tribal peoples remained much the same as it had under the Principate. There does not seem any good reason to suppose that the tribal confederations which periodically appeared were any greater than the ones which had at times faced earlier Roman armies. Certainly at a strategic and tactical level, the military practices of the barbarian tribes had remained essentially unchanged. The limitanei were there to deal with small-scale attacks. Larger incursions, made by several hundred or more warriors, could not be stopped, and so it became a question of seeking refuge in forts or fortified towns and either waiting for relief or to harass the enemy when the latter decided to leave. Battles were rare on these frontiers as well as in the east. The Roman objective was to move quickly and strike suddenly. Whenever possible, barbarian raiders were ambushed or taken by surprise, so that their defeat was made as certain as possible and Roman casualties were kept to a minimum. The acknowledgment that many attacks could not be stopped before they reached the settled parts of the provinces was in some respects a change from the earlier period, but in essence most of the principles of frontier warfare remained the same. If the Romans were perceived to be weak then they would be attacked. Frontier defence was still primarily based on creating a facade of overwhelming power which deterred raids in the first place. This was done through a combination of diplomacy, emphasis on inflicting heavy losses on raiders, even if this was done as they withdrew, and aggressive expeditions into the tribal heartlands to instil fear of Rome’s military might. On the whole the army performed this task well until the beginning of the 5th century. Yet bouts of civil war weakened the army, even if only temporarily, increasing the chance of minor defeats on the frontiers. Every such defeat, however small, diminished respect for Roman military might, if it was not speedily avenged.

The Arch of Septimius Severus, Rome, commemorated his victories in Parthia and was decorated with reliefs showing these campaigns. Unfortunately most are very badly eroded and it is difficult to make out much of the detail of soldiers' equipment.

The Arch of Constantine, Rome, openly celebrated his defeat of Roman rivals and was probably the first public monument to show dead and defeated Romans In this scene Constantine's soldiers - some of them perhaps auxilia palatina - attack a fortification. Note the large oval shields, spears and javelins.

Battles were rare events in wars against foreign opponents in all areas, although the likelihood that they would produce a decisive result ensured that many civil wars were decided by such an encounter. Whilst the smaller units of Late Antiquity were especially well suited to the small-scale mobile warfare being waged on most frontiers, they also operated effectively as part of larger armies in massed encounters. As in earlier periods, the army continued to form in more than one line, keeping at least half of the available forces in reserve. Roman generals still controlled a battle in the traditional manner, encouraging and inspiring the men from close behind the fighting line and managing the commitment of reserve units. In most respects unit tactics were similar to earlier periods, although Roman close-order infantry do appear to have been a little less aggressive. Ammianus speaks of Roman legionaries charging at a dash, in spite of the inevitable loss of order, to close the distance and sweep away Persian archers quickly, but in most other battles they tended to remain on the defensive. Forming a dense line, Roman infantry would bombard the enemy with javelins, darts, perhaps a heavier throwing-spear, and often arrows fired by archers in the rear rank. We also read of them employing the barritus, a war-cry of Germanic origin, which began with a low murmuring, the men holding their shields close to their faces to create an echoing effect, and rose to a crescendo. These tactics were in contrast to the slow, silent advance, pilum volley at point blank range, and screaming charge of the professional legionaries in earlier periods, although in many ways they were more similar to the behaviour of the older, militia army.

The late 3rd-century AD Arch of Galerius in Thessalonike, Greece, commemorated his successful war against the Sassanid Persians and contains a number of reliefs depicting soldiers. Most wear scale armour, spangenhelms and carry oval shields.

Conclusion: The army and the end of the western Empire

By the end of the 5th century the western Roman Empire was no more. In the east, emperors continued to rule for a thousand years. Much of Rome’s culture, as well as many military institutions, were preserved by the eastern (or Byzantine) Empire. Several of the key events which marked the collapse of the west were military defeats, but it would be a mistake to see the fall of Rome as primarily caused by an inadequate military system. At its best, the late Roman army was considerably more efficient as a fighting force than any of its contemporary opponents. Yet weakening central authority, social and economic problems, and most of all the continuing grind of civil wars eroded the political capacity to maintain the army at this level of effectiveness. A permanent, well-equipped, organized and disciplined professional army was a very expensive institution to support, but also a dangerous one, for no emperor could ever be fully secure when there was the slightest chance of the army backing a usurper. The Byzantine emperors managed to maintain an army which combined a reasonable level of efficiency with a fair record of loyalty, encouraging long periods of political stability which in turn brought the prosperity which permitted them to afford this force. Because of a range of factors, many beyond their control, the last western emperors were unable to achieve this balance, and the army withered along with the central government which in various forms had maintained it for so many centuries.

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