The problem first became grave in the reign of Marcus Aurelius (161-80), who had to face a collusive general onslaught from the north which plunged the Empire into its first major crisis for many years. Septimius Severus (193-211) noted the lesson and increased the size of Rome's army. He also remunerated it better. This meant, in the years ahead, fiercer taxation for the civilian population whose comparatively easy-going, comfortable lives had to be drastically modified in order to pay the 400,000 soldiers of the army.
Nevertheless, for the greater part of the third century AD the Imperial frontiers were broken by repeated and simultaneous hostile incursions, from Germans and others in the north and from Persians (the much more formidable successors of the Parthians) in the east. It seemed as if the Roman world, which was also split into fragments by internal revolts, could not possibly survive. Yet, in one of the most striking reversals in world history, Rome's foes were hurled back by a series of formidable military Emperors.
However, the price the inhabitants of the Empire had to pay was enormous. In order to raise the gigantic contributions in cash and kind that were needed to maintain an army capable of performing such feats, tax requirements continued to rise to unprecedented levels. First Diocletian (284-305), and then Constantine the Great (306-37), radically overhauled and regimented the entire administrative system in order that the necessary payments should be extorted.
Constantine, in common with other Emperors of the time, made extensive use of German soldiers and officers in his own army - at first Franks and Alamanni, later Visigoths and Ostrogoths (the two branches of the Gothic race) and Vandals and Burgundians. Moreover, like some of his predecessors but on a larger scale, he allowed German immigrants to settle under Roman supervision within the frontiers. But the military threat from German tribesmen who were still outside, as well as from the Persians at the other extremity of the border, persisted with undiminished force.
Constantine drew the conclusion that Rome was no longer a suitable capital. Living there, it would be too hard for him to maintain simultaneous control over the two vital frontiers, the Rhine and Danube in the north and the Euphrates in the east. Earlier rulers, already feeling the same, had from time to time established their residences at places more accessible to the defence zones. Mediolanum (Milan) had been a favourite choice, and Constantine himself had dwelt in a number of other centres: Treveri (Trier) in western Germany, Arelate (Aries) in southern France, Ticinum (Pavia) in north Italy, Sirmium (Sremska Mitrovica) on the Illyrian (Yugoslavian) river Savus (Save), and Serdica (Sofia) in Moesia (Bulgaria). But he now decided that the ideal site for simultaneous supervision of the Danube and Euphrates frontiers alike was Byzantium on the Bosphorus; and there he founded his new capital, Constantinople, on the site where Istanbul is today.
Constantine also put into effect a second major revolution by officially converting the Empire from paganism to Christianity -raising a relatively small and uninfluential Christian community to a dominant position in the state. Then he died, and left the Empire divided amongst his three sons, of whom Constantius n (337-61) proved the survivor. In his reign troubles on both the northern and the eastern frontiers revived sharply. Near the Rhine, his cousin Julian won an important victory over the Germans at Argentorate (Strasbourg) in 356; five years later, he came to the throne. Known as 'the Apostate', Julian reverted to official paganism. But in 363, during a Persian campaign, he lost his life, and under his successor, Jovian, the Empire returned to Christianity. However, he died in the following year.
DECLINE AND FALL
The hundred and twelve years beginning from that date, and concluding with the termination of the Western Empire, comprise the period with which this book will be mainly concerned.
The date when the Empire first began to decline and fall has long been disputed. A school of Marxist historians, with the support of Arnold Toynbee, declared that the crisis of classical civilization leading to Rome's collapse started as far back as 431 BC, when the city states of Greece were locked in hostility with one another in the Peloponnesian War - four centuries before the Roman Emperors, whose downfall this event was alleged to foreshadow, even began.
Edward Gibbon had taken a very different view, refusing to see too much wrong with the Empire at a date a full six hundred years later:
. . . If a man were called to fix the period in the history of the world during which the condition of the human race was most happy and prosperous, he would, without hesitation, name that which elapsed from the death of Domitian to the accession of Commodus [AD 96-180].
Subsequent historians have queried his assertion, pointing out that the slave population, for example, could scarcely be described as 'happy and prosperous', and that many of the things that went manifestly wrong later on were already quietly going wrong behind the scenes as early as Gibbon's supposed golden age. Yet, if we limit the 'human race' to the population of the Empire, and consider how its majority was faring, he was probably not too wide of the mark.
Subsequently, in the third century AD, under the joint pressures of external threats and internal rebellions, the Empire began to fall apart. Yet this was by no means the end, since it was only a good deal later still, as late as the turn of the fifth century AD, that the final downfall really began.
A start, therefore, with the present book will be made in the reign of Valentinian i (364-75), when this downward process was about to start: though in his day Rome still seemed to be at the height of its power.
VALENTINIAN I
In 364 the army acclaimed Valentinian 1 as Emperor, and he was the last really impressive Emperor Rome ever had. He came from Cibalae (Vinkovci) in Pannonia (Yugoslavia). He was tall and vigorous - a champion wrestler - with fair hair and bluish-grey eyes, regular features, a long face and a large straight nose. Although his enemies sneered at his barbarous origins, he was quite thoroughly educated, and a clever painter and sculptor.
His character was disconcerting: cruel, jealous, evil-tempered and panicky. Nor was he a reliable judge of the civilians he chose to govern the Empire on his behalf. Yet Valentinian was a superb soldier and a conscientious worker, endowed with ferocious energy. He felt a strong duty to the state, and, much more unusual, a strong duty to the poor, an emotion which he combined with a considerable distaste for the Roman upper class. More unusual still, in the age in which he lived, he believed in tolerating differences of religious opinion. For all his faults he would have been an outstanding man in any epoch, and it is only because of the misleading tradition which dismisses the personalities of the later Empire that most people have never heard of him.
Valentinian decided that the needs of national defence required there should not be one single Emperor only, but two. In consequence, he gave his brother Valens the East, and took the West for himself. The Western Empire that he inherited was immense, with a large army to defend it, and after his eleven-year reign he left it stronger than ever.
But this great strength had only been maintained by his own unremitting vigilance and energy. For as soon as he came to the throne, he was plunged immediately into a variety of emergencies. In the words of Ammianus, who wrote a magnificent Latin history of the later Roman Empire, 'at this time, as if trumpets were sounding the war-note throughout the whole Roman world, the most savage peoples raised themselves and poured across the nearest frontiers'. Yet Valentinian and his able generals were a match for them.
The first thing that had happened was that Germans broke across the Rhine, capturing the fortress of Mainz. But they were defeated by the Romans three times, and then the Emperor himself, moving his headquarters from Lutetia (Paris) to the frontier city of Treveri (Trier), marched up the valley of the River Neckar and won a ferocious victory in the Black Forest. He remained in Germany for seven years, constructing an elaborate system of fortifications on the Rhine, building a strongpoint at Basilia (Basel), and moving to Ambiani (formerly Samarobriva, now Amiens) in order to direct operations in Britain, which was overrun by Saxons from across the sea and Picts and Scots from the north.
Valentinian also deliberately stirred up dissension among the Germans themselves by calling to his aid the Burgundians, hereditary foes of their compatriots the Alamanni who were the enemies of Rome. Meanwhile, many Germans continued to be admitted as settlers within the boundaries of the Empire.
In 374 a more easterly section of the northern border was breached when other Germans, as well as members of the great group of Sarmatian peoples of mainly Iranian stock, erupted across the middle and upper Danube into what are now Hungary and Austria. In the following year Valentinian established his residence at Sirmium, and restored the fortresses on the Danube, which he crossed to ravage the German territory on the other side. Later in the same year the insolent attitude of German envoys who came to see him in Hungary so infuriated him that he broke a blood-vessel and died.
His son Gratian, a somewhat insignificant sixteen-year-old, became his successor, but in his absence on a different part of the frontier the powerful Roman army of the Danube attempted to set up one if its own generals as Western Emperor in his place. To prevent this, German staff officers hastily summoned Valentinian's widow Justina and her four-year-old son, who was proclaimed Emperor as Valentinian II at Aquincum (Budapest). Neither Gratian nor Valens had been consulted. But they accepted the child as joint ruler, and assigned him half of the Western Empire, comprising Italy, north Africa, and most of the Balkans.
The Eastern Empire now suffered a terrible setback, which profoundly affected East and West alike. This was the battle of Adrianople (Hadrianopolis, now Edirne in European Turkey) which had been fought against the Visigoths.
Descriptions of the various, differing Germanic peoples can be found in E. A. Thompson,
Romans and Barbarians: The Decline of the Western Empire
(1982) and J. D. Randers-Pehrson,
Barbarians and Romans: The Birth Struggle of Europe, AD 400-700
(1983). There were two great German states in eastern Europe, the Ostrogoths ('bright Goths') in the Ukraine, and the Visigoths ('wise Goths') centred upon what is now Rumania. But the formidable cavalry of the Huns, a non-German people, had broken into these regions in about 370, destroying the Ostrogothic kingdom and driving 200,000 Visigoths before them across the Danube into the Eastern Roman Empire, where the representatives of Valens allowed them to settle. However, these Visigoths very soon complained, with a good deal of justice, that they were being oppressed and exploited by the Eastern Romans, against whom they consequently rebelled. Led by their chieftain Fritigern, they devastated the Balkans, while at the same time further German tribesmen burst across the Danube in their wake. The Eastern Emperor Valens hurried from Asia to deal with the emergency, and moved to the attack at Adrianople on 9 August 378. But the Visigoths, after a successful flank attack by their horsemen, won an overwhelming victory. The Roman cavalry fled and the Roman infantry was utterly destroyed. Valens perished, but no one ever found his body.
'We might stop here,' declared the nineteenth-century historian Victor Duruy; 'the invasion has begun: Fritigern has come right up to the gates of Constantinople: in a few years Alaric will take Rome.'
THEODOSIUS I
The Western Emperor Gratian, having failed to reach Adrianople in time, moved back again into his own territories. But he also took steps to appoint a new colleague. His choice fell on the thirty-two-year-old Theodosius, the son of a land-owner of the same name from Cauca (North-west Spain) who had at one time (before falling into disgrace) been Valentinian I'S most successful general. Proclaimed Emperor at Sirmium, his son ruled for ten years in the Eastern Empire, to which the West now ceded the greater part of the Balkans. Then he became the ruler of the Western Empire as well, so that the two Empires were momentarily reunited before his death.
Theodosius, with his fine aquiline nose and hair as fair as Valentinian's, presented an elegant appearance. But Theodosius was less uniformly energetic, oscillating between passionate activity and indolence, between the simple existence of a soldier and a resplendent court life, diversified by the reading of Roman history. He liked to dole out cruel sentences and penalties, but was quick to revoke them and grant pardons. Greedy and extravagant, he wanted to please, and tried to keep his promises, though he lacked the reputation of a reliable friend or chief.
Theodosius was called 'the Great', because of the uncompromising Christian orthodoxy which characterized his reign. Its other dominant feature was the acceptance of the Visigoths
en bloc
inside the Empire (382), to live under their own laws and ruler on the condition that they provided soldiers and agricultural workers for the Romans - the first of a number of German nations to be granted such allied, 'federate' status.
Theodosius soon lost his Western colleague Gratian, murdered at Lyon in southern France by the troops of a usurper, Magnus Maximus, in 383. Four years later, Maximus suddenly invaded Italy, but Theodosius 1 defeated him in two battles, and beheaded him at Aquileia. However, in about 389, he had to yield to severe external pressure, and ceded to the Germans the western extremity of the upper Danube line north of Lake Brigantinus (Constance), near the modern border between Germany and Switzerland.
When Theodosius returned to Constantinople, he left behind, as the real ruler of the West, his Master of Soldiers or commander-in-chief, Arbogast; and in 392 it was he, in all probability, who was responsible for the death of Valentinian II at Vienna (Vienne) in southern France. Arbogast then endeavoured to assert his independence from Theodosius. Being a German, he did not aspire to the purple himself, since men of his race, however great their practical power, were not acceptable as Emperors. Instead he set up a puppet, the rhetorician Eugenius, in whose name he assumed control of Italy and the Spanish provinces.