Roman tradition held that their city was founded by Romulus in 753 вс. At first a monarchy, the kings were expelled and a Republic created near the end of the 6th century BC. Rome gradually expanded, absorbing the other Latin-speaking communities and in time other Italian peoples, so that by the early 3rd century BC, she controlled all of the Peninsula south of the Po. A long and arduous struggle with Carthage brought Rome her first overseas provinces and, by the mid-2nd century BC, undisputed dominance of the Mediterranean world. Expansion continued, but the vast profits of foreign conquest placed a great strain on the Republican system of government, causing politics to become increasingly violent. The 1st century вс witnessed a cycle of civil war and upheaval, ending only in 31 BC when Caesar’s adopted son Octavian defeated his last rival.
Octavian, who later took the name Augustus, replaced the Republican system of government with a peculiarly Roman form of monarchy, known today as the Principate. Openly he presented himself as the senior magistrate and servant of the state, but in reality he had taken over the power of all the other political institutions, including the Senate and the Peoples Assemblies, and from early on in his reign he began to mark out a successor. Augustus continued the expansion of the Empire and by his death in AD 14 it had in many places reached the frontiers that it would hold for several centuries. There were a few exceptions - Britain was invaded by Claudius in ad 43 and Trajan annexed Dacia in ad 101-06 - but the great conquests were never repeated. The Principate gave Rome stability for over 200 years, and only twice, when emperors died without a clear successor, did civil war return.
Rome grew gradually in size and splendour - most of the monumental structures visible in the Forum today, shown below, were built under the rule of the emperors Warfare played a prominent part in Roman history, and as the city changed, so did the army that fought to protect it.
In the 3rd century ad this changed, civil wars becoming as frequent as they had been in the last decades of the Republic. On average emperors lasted for no more than a few years, and the majority died violently as the army spent its strength in fighting itself. The Empire began to break up, some rulers controlling only small sections of it. At the same time its weakness encouraged foreign enemies and led to many defeats. In time the Empire split, the western and eastern halves each having their own emperor or emperors. Long-term stability never returned, though some strong rulers created decades of relative peace, yet Rome’s strength was still far greater than that of any of her opponents. The western Empire eventually collapsed in the 5th century AD, but the eastern Empire with its capital at Constantinople endured, preserving many of Rome’s military institutions until well into the Middle Ages.
Roman soldiers have often been depicted in epic films, although the accuracy of such reconstructions has varied enormously. This scene from Gladiator shows a senior officer riding between lines of legionaries and eastern auxiliary archers From a distance at least, the equipment of these men appears to be reasonably accurate and the scene certainly gives a good impression of the grubby appearance of soldiers on campaign.
The changing face of the Roman army
The Roman army played a central role in the city’s history, creating and maintaining an Empire which came to encompass Europe, North Africa and the Near East. The popular image of the army is of a highly organized, rigorously professional and savagely disciplined force run on remarkably modern lines. At least some of this picture is true for at least some periods of the army’s existence, but it conceals the massive changes that occurred in Rome’s military institutions over the long centuries of its existence. In this book we will examine the three central phases in the history of the Roman army.
We shall begin with the militia army of the Mid Republic (3rd to 2nd centuries вс), for this is the period when our sources are sufficiently good to give us a clear impression of the Roman army. It was recruited from citizens who submitted to military discipline for the duration of a war and then returned to civilian life. Soldiers were propertied men, usually farmers owning enough land to allow them to afford their own weapons and equipment. For such soldiers service in the army was not a career, but a duty they owed to the state. It was the militia army that conquered Italy, defeated Carthage, and made Rome dominant throughout the Mediterranean.
The second phase (1st century вс to early 3rd century AD) began with the creation of the professional Roman army. Continuing expansion meant that wars were being fought further and further from Italy and created a requirement for large garrisons in conquered territory. The militia system was not capable of coping with these new conditions. Instead of a prosperous farmer serving for short periods of time out of a sense of duty to the Republic, the legionary was from now on usually a poor man, viewing the army as a career. The result was a fundamental shift in the relationship between the army and state, making possible the civil wars which destroyed the Republic. Eventually Augustus took care to make the army loyal solely to himself and his family, a practice followed by his successors. Under the Principate the Roman army reached the peak of its efficiency, completing the conquest of the Empire and then preserving Roman rule. It is during this period that the Roman army came closest to its popular image.
The final phase (3rd to 5th centuries ad) covers Late Antiquity, when the professional army faced increasing external threats whilst being continually ground down in civil wars. New types of units appeared, different equipment was adopted, and the structure of the army changed as it struggled to cope. Yet in spite of all this, much remained the same and there were greater differences between the Mid Republican army and the army of the Principate than between the latter and the forces of the Late Empire.
Sources of evidence
Although the Roman army existed for an immensely long period of time, it disappeared many centuries ago and left only traces of its passing in the remains of its bases and forts, the fragments of equipment and the descriptions of its deeds in the accounts of Roman and Greek writers. Taken together, we do have a considerable body of evidence with which to reconstruct the institutions and daily life of the Roman military, but each type of source presents its own problems of interpretation. It is worth pausing briefly to consider the nature of our sources.
1 Literature: Politics and war were the two main concerns of Roman historians. History was first and foremost a branch of literature and was expected to display high levels of stylistic and rhetorical skill, sometimes at the expense of accuracy. Accounts of the army on campaign tend as a result to focus most of all on the dramatic incidents, such as battles and sieges. There were also literary themes or set-pieces (known as topoi) that educated readers expected to find in an historian’s narrative.
A gateway that is part of the extensive 19th-century reconstruction of the Roman fort at Saalburg in Germany. Such projects inevitably represent a combination of known facts recovered through excavation and a good deal of conjecture It is probable that the towers on either side of the gate ought to be higher.
At best this led the writer to select appropriate subjects for inclusion, but at worst it could lead to outright invention. Although the historians provide many accounts of the army at war, they are far less likely to describe the more mundane day-to-day aspects of frontier patrolling, policing and the many activities of peacetime.
Another result of the importance of style and readability to ancient historians manifests itself in a reluctance to include too much technical information. Topographical description, even of features of importance to a specific campaign, is often brief and vague. Detailed information about the army’s equipment, organization, tactics and logistical system are exceptionally rare, and often consist of fragments mentioned incidentally by an author. Some writers may have omitted such information simply because they assumed that it would all be immediately familiar to their audience. Julius Caesar, who left an invaluable account of the campaigns of his own army, tells us very little about the structure of the legions or their arms, never once mentioning that his men wore body armour, though we know from other sources that they did.
A 19th-century diagram of the bridge constructed by the legions to span the River Rhine in 55 вс, based on Julius Caesar's description of this structure in his Gallic Wars rather than on direct archaeological information. Our literary sources provide a good deal of information about the army, although they do not always supply us with as much technical detail as we might wish.
It is worth listing the main sources for each of our three periods and discussing their relative usefulness. For the Mid Republican army, our most important account is provided by the Greek historian Polybius who wrote his work around the 140s BC. A soldier himself, Polybius was originally sent to Rome as a hostage, where he became an intimate of the Roman general Scipio Aemilianus, accompanying him to the siege of Carthage in 147-146 вс. Polybius includes a detailed description of the Roman legions in this period, describing their organization, equipment and the layout of their temporary camps. The other major source for this period, the Roman historian Livy, wrote at the end of the 1st century вс and is far less reliable for military detail. Other sources for this period include the Greek historian Appian and the biographer Plutarch, both of whom wrote in the early 2nd century ad and sometimes preserve information from earlier sources which have not survived.
For the professional army, Julius Caesar’s Gallic Wars of his campaigns in Gaul and the civil war are invaluable for understanding the army at war. Tacitus, who wrote in the early 2nd century ad, provides us with much detail for the army of the Early Principate. The Jewish historian Josephus, who had fought against Rome during the Jewish Rebellion of AD 66 before changing sides, provides a more detailed account of a single conflict, as well as a description of the army mirroring the one provided by Polybius for the Republic.
The literary sources for the army in the 2nd and 3rd centuries ad are few and rarely reliable. For part of the 4th century, Ammianus Marcellinus provides an exceptionally detailed account of large-scale invasions and sieges as well as relatively small- scale raiding. A staff officer himself, Ammianus had actually witnessed some of the events he described.
A face mask from a Roman helmet excavated at Kalkriese in Germany, most probably the site of the Teutoburg Wald, where an entire army of three legions was wiped out in ad 9. The analysis of finds of military equipment has allowed the emergence of a much clearer picture of the appearance of Roman soldiers. However, this does not mean that it is always straightforward to interpret this evidence. It has normally been assumed that face masks were only worn on parade or for certain ceremonies, and yet this item was found on a battlefield.
A genre distinct from history, though just as much considered primarily a form of literature, was the theoretical manual, several of which have survived. For the army of the Principate we have Frontinus’ Stratagems, a collection of ploys used by generals in the past, Arrian’s Battle Order against the Alans and Tactics, and Pseudo-Hyginus’ On the Construction of a Camp. Near the end of the 4th century Vegetius produced his Concerning Military Affairs which drew upon many earlier sources and presents an often confusing patchwork of different periods and perhaps some pure invention. All of these sources are useful, but it is important to remember that theoretical works were inclined to depict the army as it should ideally have been, rather than necessarily as it actually was.
(Above) Aerial view of the Roman camp facing the Iron Age hillfort at Burnswark in Scotland Shot from artillery and sling bullets were found around the gates of the hillfort. For a while a number of scholars argued that this camp was established after the hillfort had been abandoned and was used as a training area by the Roman army. However, most now believe that this was the site of a genuine siege and not simply routine training Such controversies illustrate how difficult it can be to interpret archaeological evidence.
2 Archaeology: Our literary sources have been known and studied for centuries, and it is now extremely unlikely that any new text will ever be discovered. By contrast, archaeological excavation offers an ever-expanding resource and has contributed massively to our understanding of the Roman army. A huge number of military sites have been identified and many partially excavated, though few auxiliary forts and no legionary fortresses have undergone full excavation. Military equipment and traces of the presence of soldiers also occur on sites less immediately associated with the army.
It is rare to find much trace of the army on campaign, still less of the many battles it fought and very, very few battle sites can be positively identified, though the recent excavations of the disaster in ad 9 in the Teutoburg Wald in Germany are an exception. During sieges, which lasted longer than battles, the army often constructed substantial works in the form of surrounding ditches and ramparts, temporary forts, or assault ramps, and these have sometimes survived. Such siege lines have been found at Numantia (Spain), Alesia (Gaul), and Masada (Judaea) amongst other sites. A few places have also revealed evidence of the army’s ferocity when it captured an enemy stronghold, most notably the gruesome skeletons found at Valencia in Spain and Maiden Castle in Britain. Taken together, the archaeological evidence for the Roman army at war is very slim. Archaeology is far better at revealing cameos of life in a certain place at a certain period, and taken together the evidence from many sites allows us to discern longer-term trends. A solidly constructed base occupied for decades or even centuries by the army will inevitably produce far more evidence than a marching camp occupied for a single night. Excavation can reveal the size and layout of a base, hopefully the date of its foundation and of any significant subsequent re-buildings or changes in its structure. It will not explain why the site was chosen, whether the buildings were always fully occupied or what the garrison was doing.
3 Sub-literary sources - papyri and writing tablets: Some texts have survived directly from the ancient world to be discovered by archaeologists, unlike the works of the ancient authors which exist because they have been copied time and again over the centuries. In the eastern provinces, especially those with hot, dry climates such as Egypt, many military documents and private letters to or from soldiers have been preserved on papyrus. In Europe similar documents are beginning to crop up on wooden writing tablets, most famously at the fort of Vindolanda in northern Britain. These texts are concerned primarily with day-to-day life and the routine of soldiering. Some are concerned with the administration of a unit, such as strength reports, inspections of equipment, or applications for leave, whilst others represent private correspondence. Neither these, nor the texts dealing with business transactions or legal disputes, deal with the great events described by the historians or the long-term trends revealed by archaeology. In most cases these were issues and actions only of significance to those immediately involved. Yet more than anything else these documents tell us what it was like in an army garrison.
4 Epigraphy: Another major source of evidence is provided by inscriptions in Greek or Latin erected by units or individual soldiers. Official inscriptions were often set up to commemorate the completion of building work, and where we are fortunate enough to have these they allow us to date precisely such projects. Religious inscriptions, very often on altars, can tell us a good deal, and not simply about the soldiers’ beliefs. Individuals often mention their rank and unit and sometimes we also have altars dedicated by an entire unit led by its commander as part of the army’s formal religion. The other most significant type of inscription is the tombstone or memorial, many of which list a soldier’s unit and service record and occasionally the details of his career. Much of our understanding of the rank structure and system of promotion in the army comes from the epigraphic record.
Care needs to be taken when interpreting inscriptions as with any other source. They tell us definitely no more and no less than their text, that such and such a unit built a new gateway, that an officer dedicated an altar to a local deity, or that a man died at the age of so many years after a period of military service and served in this unit and that rank. From evidence of this sort we try to infer many things, for instance the identity of the unit in garrison at a fort, or the ethnic background of its soldiers, based usually on their name and perhaps the god or goddess they chose to venerate. Yet much of this must remain conjectural, and all we really have is attestation that a unit carried out a task in that place when this is specified, or that an individual had an altar erected or died in that place.
Fragments of a letter written on a wooden writing-tablet found at the site of the fort at Vindolanda and dating to the end of the 1st century ad. Such material will only survive in certain conditions, but already similar documents have been found at other sites in northern Europe The Vindolanda tablets include official and unofficial correspondence of the fort’s commanding officers, as well as many documents connected with the army's administration.
5 Art and sculpture: Archaeology has provided us with many examples of some types of Roman equipment. Metal pieces - helmets, armour, weapons, belt buckles, harness decoration, etc. - are comparatively plentiful, but leather items, for instance boots or belts, are rarer, surviving only in certain conditions. Textiles, including clothing of all types from cloaks to tunics to socks, hardly ever survive and then only in the most fragmentary form. Therefore, in order to gain a clearer picture of what Roman soldiers actually looked like, we need to employ the images of soldiers depicted in various forms of art, from mosaics and wall-paintings to sculpted figures on coins and monuments.
(Above) Another useful source of information concerning military equipment comes from tlie depictions of soldiers on their tombstones This stone commemorated Flavinus, a standard-bearer of the Ala Petriana, and is now in Hexham Abbey, Northumberland. He is shown wearing a crested helmet, and carrying a standard.
A relief from the early 2nd- century AD Tropaeum Traiani at Adamklissi in Romania showing three standard- bearers. Each man wears mail armour, and two carry a square vexillum flag, while the man in the centre bears a signum. The signum was the standard of a century and was carried by an officer known as a signifer. This monument was constructed by the army itself and includes many details of the equipment actually in use rather than the more idealized portraits of soldiers on such official monuments as Trajan’s Column.
Trajan’s Column was erected in Rome to commemorate that Emperors victory over the Dacians in AD 106 and is inscribed with scenes forming a narrative of the campaigns. It is a celebration of the army as much as of the Emperor who led it and depicts an ideal Roman army, the different troop types all in their regulation uniforms. The contemporary Tropaeum Traiani at Adamklissi in Romania was built by one of the provincial armies that had taken part in the same set of wars and depicts their part in it. This is very different in style from the more sophisticated column in Rome, showing local variations in weapons and equipment, and probably more closely depicts what the soldiers actually looked like. Other columns and arches depicting the army have survived, though none quite rival these for detail, accuracy and high state of preservation.
On a smaller scale, but no less important, are the many representations of soldiers such as those found on some tombstones. These present the image that the soldier or his commemorators wished to project, which is not always the same as the official view seen on the larger monuments. In some cases equipment is represented in great detail, though in others the men chose to be shown in undress uniform without armour or weapons.
Bringing the sources together
The different sources together provide us with a great body of information, from which we can attempt to build up a picture of the Roman army. However, we should never forget that our evidence represents a tiny fraction of what was once available. The majority of histories, biographies and military manuals written in the Roman period have not survived even in a fragmentary form. The subliterary texts hint at massive amounts of written military records and thriving exchanges of correspondence, but preserve only a statistically insignificant sample of this. Though we have a good number of military tombstones, infinitely more men who served in the Roman army left no such memorial to themselves. Excavation of military bases has tended to deal with only a small proportion of each site and some wider projects have proved very surprising in what they revealed. The study of any aspect of life in the ancient world, including the Roman army, involves making the best of a limited amount of information.
Nor is this information evenly spread. Literature leaves almost blank the greater part of the 2nd and 3rd centuries ad. The archaeological evidence, along with the epigraphic record, tends overwhelmingly to come from the professional army of the Principate and, to a much lesser degree, Late Antiquity. The militia soldiers of the Mid Republic were still the Roman people under arms. At the end of the campaign they returned to normal life not to purpose-built barracks, and blended back into the wider population. Such a force left little distinct trace archaeologically.
Each type of source provides us with a slightly different perspective on the Roman army and contributes towards the creation of a broader picture. However, we should not expect the different types of information always to fit together neatly and seamlessly. It is certainly a mistake to interpret one type of source from the perspective of another. The different phases discerned in the layout and size of a fort should be dated and explained on their own merit and not forced to conform to some wider view of policy within that province. Where such correspondence does appear to emerge, it is best that the complementary interpretations grow up independently. It is salutary to recall that Hadrian’s Wall, probably the most substantial and certainly the most intensively studied frontier monument of the Roman army, is mentioned only a handful of times in extant Greek and Latin literature, and its purpose never clearly explained. The Roman army was a large institution that remained in existence for many centuries. We should not be dismayed if different sources appear to suggest very different practices within it. It is doubtful that we can guess at the real complexity and at the great variations over time and in different parts of the Empire of the real thing.