For a five-hundred-year period beginning in 100 b.c. With Marius’s and Sulla’s defeat of the massive tribal invasions of the Mediterranean world by the Teutons and the Cimbri, the Romans ruled the northern frontier of their world, an empire that stretched across europe from the mouth of the Rhine to that of the Danube. On the other side of the Rhine lay fierce warrior tribes, which from time to time posed serious threats to the empire’s security. Yet for all their fierceness, the tribes were consistently defeated by Rome’s legions. There were military defeats, of course, such as the massacre of Teutoburger Wald, but from the crushing of the Teutons and the Cimbri, the Romans enjoyed an astonishing record of destroying the armed mobs that characterized the German approach to war.
From the rise of Octavian Caesar, later titled Augustus, to supremacy over the Roman world in 32 B.C. with his defeat of Mark Antony, a professional army of between twenty-five and thirty-three legions (approximately 150,000 legionnaires and 150,000 auxiliaries) defended the empire from Hadrian’s Wall in northern Britain to the upper Nile and from the Strait of Gibraltar to the Euphrates River in Syria. This indeed was an extraordinary example of economy of force. What explains this stunning military effectiveness?
Above all, Roman military effectiveness depended on the discipline and training of the legionnaires, the hallmark of a professional military organization in the modern sense. Flavius Josephus, the great historian of the Roman-Jewish War of A.D. 66–70, described the Roman training regimen in the following terms:
And indeed, if anyone does but attend to the other parts of [Roman] military discipline, he will be forced to confess, that their obtaining so large a dominion hath been the acquisition of their valor, and not the bare gift of fortune: for they do not begin to use their weapons first in time of war, nor do they put their hands first into motion, having been idle in times of peace; but as if their weapons were part of themselves, they never have any truce with warlike exercises; nor do they stay till times of war admonish them to use them; for their military exercises by no means fall short of the tension of real warfare, but every soldier is every day exercised, and that with real diligence, as if they were in time of war, which is why they bear the fatigue of battle so easily; … nor would he be mistaken [who] would call their exercises unbloody battles, and their battles bloody exercises.
In short, the Roman army with its legions and auxiliaries was the first true professional army in history, one that relied in battle on its discipline and training rather than on the psychological glue of culture and familial and social relations. In other words, it trained as it fought.
The resulting superiority allowed the Romans to dominate their world for two and a half centuries. But things fell apart in the first half of the third century. Unfortunately for historians, there are few written records for this crucial period. Between 31 B.C. and A.D. 211, excluding emperors killed in the two major civil wars, ten emperors died of natural causes and only three were assassinated by their officers or soldiers. However, in the forty-year period between A.D. 235 and 275, only one emperor died of natural causes, while no fewer than ten were assassinated by their officers or killed by barbarians, the majority via the former mode.
In effect, the armies and ambitious generals tore the empire apart, while great barbarian invasions ravaged much of its territory. The problem was that of legitimacy in the transition from one emperor to the next. The great Roman historian Tacitus had suggested that the root cause of the civil war of A.D. 69–70, the year of the four emperors, was that the legions had discovered the secret of empire—namely, that they could choose the emperor. In fact, Tacitus was wrong for a substantial period of time, but beginning in A.D. 235 with the assassination of the emperor Severus Alexander, his assessment holds true, as the armies of Rome destroyed the economic and political stability on which the empire had rested, nominating one general after another to wear the purple and ravaging the broken body of the empire.
Finally, beginning with the ascension of Aurelian in A.D. 270, a series of emperors, most of them from the Balkans, brought a semblance of stability to the empire. Militarily, the Romans drove the barbarians from the empire’s territory, and the seemingly endless insurrections by the field armies came to a halt. But the empire was in a weakened state. Because of the loss of tactical superiority, occasioned by the weakening of discipline, the armies were less militarily effective, which in turn required a near doubling in their size. More soldiers failed to bring greater security, while the destruction wrought in the third century by barbarians and civil wars had harmed the empire’s economic structure and thereby its long-term ability to support its armies. Nevertheless, as late as 357, the emperor Julian commanded an army of 13,000 Roman soldiers against a confederation of German tribes led by the kings of the Alamanni with 35,000 warriors. At the Battle of Strasbourg, Julian’s army crushed the Germans. When it was over, 6,000 dead Germans littered the field and thousands of others drowned while trying to swim the Rhine. Roman dead numbered only 264. The victory was one more in the long string of victories that the Romans had won against the Germans despite never having successfully conquered Germany itself.
But Julian overreached himself. After Strasbourg and the death of his cousin Constantius II, he gained complete control over the empire and determined to invade the Sassanid Persian Empire. In 363, he moved with a substantial portion of the empire’s armies to the east, where the Romans advanced to the gates of Ctesiphon, the Sassanid capital. Thereafter matters did not go well, and in the midst of the campaign Julian was killed, probably by the Persians, although some ancient writers ascribed his death to a disaffected Christian, embittered by the emperor’s apostasy. The empire then fell to one of Julian’s generals, a certain Jovian, who patched together a humiliating peace with the Sassanids. Jovian promptly died, to be succeeded by one of Julian’s more successful generals, Valentinian. Barely a month after acceding to the throne, he appointed his brother Valens co-emperor in charge of the Eastern Roman Empire, while Valentinian took charge of what appeared to be the more threatened provinces in the west. And here is where the troubles began, for although Valentinian had had considerable military experience, his brother had had little.
In the late fourth century, the empire confronted a number of major threats on its borders. On the eastern frontier were the Sassanid Persians, who for nearly 150 years had contested the frontier zone between the empires and who on occasion had even invaded Syria. To the north, a fearsome enemy had appeared in the third century—the Goths. For the past one hundred years, Gothic tribes had represented a significant threat to the empire’s security. In the 260s, in the midst of Rome’s most difficult period of civil wars among rival claimants to the purple, the Goths had launched a massive invasion of the Eastern Roman Empire. They had laid waste to most of the Balkans and reached all the way to the Aegean. The economic damage was such that confidence in the coinage collapsed under a massive wave of inflation, which turned the empire from a moneyed into a barter economy. Nevertheless, once the soldier-emperors of the late third century had returned stability to the empire, the Romans proved more than capable of handling the barbarians. Constantine the Great had smashed the Gothic tribes in an extensive campaign across the Danube in the last years of his life and imposed a harsh peace on the survivors. But the Goths had eventually recovered and again represented a latent threat to the empire’s security.
If the threats posed by the Persians in the east and the Goths across the Danube were not sufficient to make Valens’s life miserable, one of Julian’s relatives, a certain Procopius, apparently with some connection to the army, proclaimed himself emperor, and Valens faced civil war in his portion of the empire. Within a year of his accession, Valens was able to crush the pretender, but the incident undoubtedly made him suspicious of the army’s loyalty to his person and position. Yet at the same time, he needed his military forces, because the Eastern Roman Empire confronted threats almost immediately from the Goths in the north and the Persians in the east, although the latter appeared the greater threat for much of his reign.
Valens chose to deal with the Goths first for reasons that remain obscure. He launched two major campaigns in 367 and 369 against them on the northern side of the Danube in the area where much of modern-day Romania lies. The Romans laid waste to great swaths of the countryside, but unlike Constantine, Valens was never able to bring the Goths to battle. The tribes took the simple expedient of sheltering in the depths of the Carpathian Mountains and lived to fight another day. After the campaign of 369, Valens concluded peace with the Goths and turned his attention to the eastern provinces, where the kingdom of Armenia with Persian help was causing significant difficulties. Initially, the Romans, helped by tribal incursions into Persia’s eastern domains, addressed the strategic problems associated with their client kingdom of Armenia without much difficulty. Still, the conflicts with the Persians kept Valens’s attention firmly on the east and away from the Danubian frontier. In 375, the Persians returned from their own eastern conflicts to mix again in Armenian politics. Both sides began to prepare for a major war. To add to the complexities of the empire’s politics and strategic situation, Valentinian died that year, leaving his young son Gratian as emperor in the west. Thus, Valans had to deal with a new opposite, young and untested, with whom he had only the relatively tenuous blood tie between uncle and nephew.
While Valens was dealing with the empire’s eastern troubles, a serious threat was arising on the Danube. For millennia, difficulties deep on the steppes of central Asia, whether caused by overpopulation or by major climate changes, had resulted in great tribal migrations. Those migrations, like a row of dominoes, had pushed tribes one after the other farther to the west. Another great movement of tribes had begun in the middle of the fourth century. The appearance of the Huns on the outer boundaries of Europe somewhere in what is now the Ukraine during the last half of the fourth century had placed huge pressure on the Goths. In 376, the Gothic tribes had appeared on the Danube and requested asylum and protection within the Roman Empire’s frontiers.
Deeply involved in his preparations for war with the Persians, Valens found himself on the horns of a dilemma. On one side, the Goths could provide substantial manpower to the empire’s hard-pressed military forces. On the other, much of the Eastern Roman Empire’s disposable military forces were concentrated on the Persian frontier in preparation for war against the Sassanids. Thus, the question of who was going to control the Goths once they were admitted to the empire and ensure they settled in depopulated areas and provided soldiers presented a major political and military problem.
The Romans, given the Gothic numbers and their own needs, agreed to allow one of the major tribal groups, the Tervingi, but not the other, the Greuthungi, to cross the Danube near its mouth—not far from where Augustus had sent the poet Ovid to exile and eventual death. Unfortunately, the Roman officials on the scene proved venal, corrupt, and militarily incompetent. They stole much of the money and grain provided to take care of the Goths. Moreover, those Goths remaining on the northern side of the Danube crossed to back up the Tervingi.
The Roman commander on the spot, Lupicinus, appears to have been an especially murderous, corrupt, and incompetent governor even by the standards of the time. He invited the Gothic leaders Alavivus and Fritigern to a banquet at his headquarters in the city of Marcianople, where he planned to murder them. But matters got out of hand. The Romans succeeded in murdering only the tribal chieftains’ bodyguards before the barbarians at the gate rioted and attacked the Romans who were guarding them. Lupicinus panicked and let the barbarian chieftains go. To add to the political disaster, he then took what forces were available and attacked the Goths. For his troubles, the Goths massacred his soldiers, while Lupicinus escaped to the unhappy fate of having to answer to the emperor for the fact that a mass of enraged Goths and their even more furious leaders were now loose south of the Danube, not far from Constantinople.
The Romans now had a full-scale emergency on their hands, one that they were going to have to address as quickly as possible. In the meantime, the Romans in Thrace to the east of Constantinople had to hold off the Goths as best they could, while the armies of the Roman Empire east and west redeployed to meet the threat south of the Danube. To make the situation even more dangerous, other barbarians on the north side of the river crossed to join up with the Goths, hoping to participate in the looting of the Balkan provinces. Moving south from Marcianople in 377 all the way to Adrianople and the Aegean, the Goths took their measure of revenge for the extraordinary ill-treatment they had received from Roman officials. The only areas that remained outside the reach of the pillaging barbarians were the cities and fortified towns, which were preserved by the Goths’ lack of tactical expertise in siege warfare. The invaders, mostly young warriors eager to make a reputation among their peers, wrecked, burned, murdered, and raped everything in their path.
One of the extraordinary trends in recent academic historiography is the argument that the invading tribes inflicted little systemic damage as they moved into the empire. Only academics who have spent their entire lives sequestered in school and with scant knowledge of the real world could gin up such nonsense. In fact, the rapine, murder, and pillaging that the Goths inflicted on the countryside of course represented an unbelievable catastrophe for their immediate victims and in the long run for the empire itself by destroying the infrastructure and rural base on which Roman urban life depended. The historian and soldier Ammianus Marcellinus recounts what befell the civilians in the path of the Gothic fury once the tribes broke through the Roman armies into the plains of Thrace:
The moment that … the passage of these defiles was opened, the barbarians, in no regular order, but wherever each individual could find a passage, rushed forth without hindrance to spread confusion among us; and raging with a desire for devastation and plunder, spread themselves with impunity over the whole region of Thrace, from the districts watered by the Danube to Mount Rhodope and the strait which separates the Aegean from the Black Sea, spreading ravage, slaughter, bloodshed, and conflagration, and throwing everything into the foulest disorder by all sorts of acts of violence committed even against the freeborn. Then one might see, with grief, actions equally horrible to behold and to speak of.…
For Valens, the crisis put his other difficulties in the shade. He now had a full-scale war on his hands. The first order of business was to accept a humiliating peace with the Persians and move the bulk of the Eastern Roman Empire’s military forces back to Constantinople to take on the Goths. But the speed of reaction of the Roman military forces in 377 depended entirely on how fast their armies could march and, equally important, how efficiently the empire’s logistic system could supply them on the march—a time-consuming and difficult process in the best of times, and this was not the best of times. It would take the Romans much of 377 to reallocate their forces from Syria and Palestine to the Balkans. At the same time, Valens requested help from his nephew Gratian, who willingly promised to bring a substantial portion of the western armies to the Balkans to support the war against the Goths in 378.
Gratian would find that a difficult promise to keep. The barbarians on the other side of the Rhine discovered what was afoot, and, led by the Alamanni, a substantial number of them crossed the frozen river. The Romans stopped the initial thrust cold in February 378. But then Gratian and his military advisers decided that they needed to launch a preemptive campaign to eliminate the possibility of further incursions across the Rhine. This made it necessary for Gratian to recall troops that had already begun to move into Pannonia on their way to the Balkans and instead concentrate those forces for a thrust across the Rhine to block the Alamanni’s plans to move into the empire. Gratian’s campaign was successful, but it delayed the movement of Roman forces to the east until later in the summer at the earliest. Yet even with this major delay, the western army was well on the way to support Valens when he moved out to confront the Goths.
Over spring 378, Roman forces recalled from Syria and the southern Caucasus, where most of them had been preparing for the war against Persia, began to flow into the area around Constantinople, the city Constantine had founded and made co-capital with Rome. Their movement depended to a considerable extent on the onset of spring and the grass-growing season that fed their animals. Valens himself had remained in the east until the last moment and had not arrived in Constantinople to take charge of his gathering military forces until the end of May 378. The emperor was not popular with the populace, since he was an Arian Christian, while the city was largely Catholic. Thus, after remaining in the capital for barely a week, he established his headquarters outside of the city on the road to Adrianople, at one of his summer palaces.
Initially, the Romans followed a strategy of attacking the warrior bands that were still ravaging Thrace. Northwest of Adrianople, a Roman column under a general named Sebastianus caught sight of a party of barbarians. It is indicative of the fear and paranoia gripping the region, as well as the reputation that Rome’s soldiers had acquired for their treatment of civilians, that the urban authorities at Adrianople refused to allow the Roman soldiers entrance to the city. Only after lengthy discussions did they finally permit Sebastianus to enter, but without his soldiers. Having wrangled a minimum of supplies out of the townspeople, Sebastianus then pursued and caught up with one of the pillaging column of Goths, who were heavily laden with booty, and slaughtered them. That small victory undoubtedly reinforced Roman confidence that once the army forced a battle on the Goths, it would win, as Roman armies had almost always done in the past.
In the short term, such Roman counterraiding parties achieved considerable success. But their successes, as well as intelligence that the Romans were gathering forces north of Constantinople, led the Gothic king Fritigern to concentrate the tribes in response. By early summer, Valens had moved much of his army up to Adrianople, where he planned to await the arrival of his nephew and the supporting army from the west. Fritigern then attempted to move his tribesmen between the Romans and their supply lines behind Adrianople, but the Romans preempted that move.
