1. The economic structure of the later empire
2. Cities and city territories
3. The army, roads, and land communications
4. Sea routes and harbors
5. The annona and the food supply of Rome and Constantinople
6. Late Roman trade
7. Technological developments and water power
8. The monetary system
10. Taxation and the empire
11. The great cities and the imperial economy
12. A survey of Rome, Constantinople, Alexandria, Carthage, and Antioch
Roman culture spread across the empire between the time of Augustus and the tetrarchy. The most striking aspect was an extraordinary level of uniformity which was stamped across the diverse regions from the Euphrates to the Atlantic seaboard. Almost all of the region was now urbanized. Cities and towns were found throughout Asia Minor, the Near East and the Mediterranean basin, across northwest Europe to the Rhine and into Britain, through the Balkans up to and beyond the Danube, and as far south as the desert and mountain fringes of Africa. By modern standards these cities were usually small, only rarely with more than 10,000 inhabitants, but as centers of economic exchange and local administration they were the key to the empire's organizational structure. They also provided places of entertainment and display. Display was particularly important in the political culture of the empire. Local landowners and other members of the wealthy classes showed themselves off and lived their public lives in these urban settings. They were also the focal points where imperial power was demonstrated to the empire's subjects. This resulted in one of the distinctive aspects of the Roman Empire, the culture of local aristocrats, whose wealth and authority was paraded in public buildings, often paid for out of their own funds, in statues for them and members of their families, and in grandiloquent inscriptions which praised their achievements. The emperors’ might was also symbolically encapsulated in temples, sanctuaries, and other monuments to the imperial cult, also associated with inscriptions, which were set up in great numbers to commemorate particular events and achievements. The need to display resources and power through intelligible visible symbols was perhaps the most important reason for the development of the epigraphic habit, the culture of inscriptions that is such a telling feature of Roman civilization.
The smaller cities of the Roman Empire could never have existed in isolation. On the one hand, they were symbiotically inseparable from the rural territories which supported them, and where most of the population of the empire lived. Both the normal Latin word, civitas, and its Greek equivalent, polis, denote not the city in the narrow sense of an urban settlement, but the fusion of town and territory, its inhabitants and institutional structures. They represent an idea or a concept, not simply a place of habitation. On the other hand, cities were interdependent with one another. This was not merely a matter of crude economics, in that they often relied on other places for sustenance and survival, but rather that they thrived as part of a system. Being a city was a mark of status, and status is a worthless commodity without the opportunity for comparison. A city in isolation would lose most of its raison d’être.
The security of the empire was guaranteed by military power. During the late empire military pressures from external enemies and from civil war increased seriously. As a result military aspects of the empire became more apparent. The distinction between peaceful provinces and narrow, militarized, frontier zones, which had been the ideal of the so-called golden age of the second century, gave way in the third century to a picture in which the difference between militarized and civilian zones, between soldier and civilian, and indeed between war and peace was blurred.1
There were however limits to Rome's military presence. Soldiers and the infrastructure necessary to support them could only be deployed on the basis of transport and communication systems. Effective imperial power was strictly determined by the network of road and sea communications which the Roman state had created and maintained. Paved roads linked the various regions around the Mediterranean with one another and criss-crossed provinces in networks that became denser and more pervasive as the empire evolved. Roads made it possible to move troops, officials, and administrators over long distances as swiftly as the conditions of a pre-mechanized age allowed. In this way rapid military deployment, the most important instrument of conquest in the hands of great generals such as Alexander, Pompey, or Julius Caesar, could be transformed into a routine of empire. This was never more evident than in the third and fourth centuries, a great age of road building,2 when troops and generals were ceaselessly shuttled to confront trouble between the eastern and northern frontiers, or when rivals for power mobilized and marched their armies across the length of the empire to achieve their purposes.
Roads, however, were exploited to serve the empire in other ways. Provincial networks underpinned and sustained the urban settlement pattern. They ensured that towns were not isolated from one another and thus the city-based culture thrived. They also provided access to isolated rural areas and they were the conduits along which rural products could be moved into towns, or collected as a form of taxation and used to support armies. All major Roman roads were furnished with a regular system of way stations (mansiones, mutationes), where official road users could stay, where mounts could be changed, and wagons maintained. Supplying means of transport for official use was one of the most important services which the Roman state expected of its subjects. Cities were required to provide pack and draft animals, wagons, and other support for military and official traffic passing through their territory. This operated on a relay system, which was one of the keys to imperial power. Travelers with authorizing documents (which were known in the late empire as evectiones), and (it must be said) a good many others without authorization, were able to requisition local mounts and draught animals until they reached the boundaries of city territories. At this point the burden and responsibility passed to the next city. In a literal sense, the horse power supplied by the cities ensured that the roads of the empire could be used to their full potential.3
The Roman Empire saw a prodigious increase in inter-regional mobility. This is confirmed by plentiful evidence from archaeology, epigraphy, and written sources for natives of one region moving to distant parts of the empire. This movement of peoples also contributed to a homogenization of imperial culture. However, the overland transport of products, especially bulky goods, was much more problematic. Local traffic, from farms and villages to the nearby town or market center will certainly have been intense, but the costs of land transport were high, and in practical terms simply unfeasible. It has been well put that a yoke of horses or oxen pulling a wagon loaded with grain would be likely to have eaten the load (or its equivalent) before they had traveled a hundred miles. Accordingly, overland inter-regional trade by private merchants was largely confined to non-bulky, high-value commodities. The Roman state was able to solve this problem through its power to requisition transport from local communities and create the relay system. This was beyond the capacity of even the wealthiest private producers and merchants.
Transport by sea was as important as land communication, and the Roman Empire witnessed an extraordinary explosion of mercantile activity in the Mediterranean. Seafaring was a dangerous activity, especially during the winter, and this confined the Mediterranean sailing season to the months between March and October. But the advantages of sea transport were overwhelming. Bulky goods could be moved over long distances in cargo vessels at costs that were a fraction of the real price of land transport; the wind may have been dangerous, but it did not have the appetite of draught animals. Marine traffic shaped the appearance of the Roman world. Coastal cities, with good harbors, were not dependent on a small hinterland for their food supply, but could import goods, at least potentially, from the entire Mediterranean and Black Sea region. In consequence settlements on the coast could grow to be much larger than those of the interior. The most populous cities of the Mediterranean world in antiquity – Rome, Constantinople, Carthage, Alexandria, Antioch, and Ephesus – were all directly on the coast or could be reached by a short riverine connection from their harbors. The Roman state organized sea transport as it had overland traffic, not by creating relays but by deals and contracts with large merchant shippers. Above all, the enormous population of Rome itself had to be supplied with imported food; the harvests of the Nile Valley, brought by transport ships from Alexandria, and of the grain fields of North Africa, imported from Carthage. Oil came from Libya, Tunisia, and Southern Spain. The mercantile infrastructure needed to feed Rome had a tremendous impact on the coastal regions of western Italy. Ostia, the harbor town at the mouth of the Tiber, was developed into the Rotterdam of the ancient world, with huge harbor works built by the early emperors, especially Trajan. A major secondary unloading point for the transports from Alexandria and the eastern Mediterranean was Puteoli in the Bay of Naples, now linked by a canal and coasting network to Rome. Docks, harbors, granaries, and storage facilities were built at intermediate points along the long-distance sea routes.4 In the late empire, the sea routes to Rome were eclipsed by comparable networks for the supply of Constantinople, which was also sustained by foodstuffs brought by the imperial annona system, responsible for supplying a significant part of its population with grain, wine, oil, and other products.
Private merchants at sea did not face the practical constraints which restricted overland trade, and there was an enormous growth in traffic. The melancholy reflection of this is the high proportion of Roman wrecks that have been found in the Mediterranean compared to those of earlier or later periods. These, however, are a crucial boon to the study of the Roman trading economy. Each preserved and excavated wreck is effectively a time capsule, preserving an atomized fragment of the Roman economic system at the moment when disaster struck. Most merchant ships carried amphoras, closely packed below the decks, containing grain, olive oil, wine, fish sauce, and other staple commodities. The study of amphoras, taken together with the wrecks where many of them have been discovered, is the lynch-pin of archaeological investigation of the Roman economy. It is also important to recognize the importance of inland water transport, both along large navigable rivers (most notably on the great rivers of Gaul and on the Po in northern Italy) and along canal systems which began to be built in all parts of the empire from Britain to Egypt and Asia Minor.
The creation of the road system and the intensification of maritime trade also reflected technological advances in the building of ships, harbors, lifting devices, and warehouses, and in the design and mass production of carts and wagons. The most critical development of the Roman Empire was the harnessing of water power to generate the energy needed for grain mills and in the mining industry. The scale and impact of technological advances in classical antiquity have been consistently underemphasized until recently in modern scholarship. The reason for this is that the most familiar literary sources, on which scholarly work has been mainly based, were produced by members of the educated elite of the classical world, who rarely took any notice of the march of technology, a subject that fell beneath the level of their gaze. On the other hand a considerable body of technical literature survives from antiquity, and this is now supplemented by an abundance of archaeological evidence for technological developments. The sophisticated harnessing of water power underpinned large scale mining and ore-processing enterprises (especially in Spain in the first and second centuries) and quasi-industrial processes such as the cutting of marble blocks and large timbers with mechanical saws, as well as grain milling.5 Mining for precious metals remained an important preoccupation of the late Roman economy, although it is evident that the disruption caused by the barbarian invasions and occupation of the Spanish provinces brought an end to large-scale mining, and probably contributed very substantially to the impoverishment of the western empire.6 In the eastern empire, by contrast, there was a growing awareness in the upper levels of society of the importance of practical technologies and their value both in economic and military contexts. This is illustrated strikingly by the sustained interest shown by Procopius in feats of engineering, mechanical ingenuity, and technological innovation, which has even led a scholar to suggest, implausibly, that his educational background and training might have been that of an engineer not a lawyer.7
The Roman Empire was also united by a uniform monetary system. With only marginal exceptions all the precious metal coinage which circulated in the Roman Empire was produced under Roman supervision to a Roman standard. In the early empire the silver denarius was the principal denomination. Roman silver coin was minted at regional centers across the empire, from Lyon in Gaul to Alexandria in Egypt, and probably mostly entered into circulation in the form of soldiers’ pay. Gold was minted much more sparsely, mostly for special occasions. A significant proportion of Roman gold coin was distributed in the form of gifts or subsidies to barbarian kings and chieftains outside the empire, and was used as a diplomatic tool in maintaining the security of the frontiers. Bronze coin in the western part of the empire was also an imperial monopoly after the first century AD, but the Greek cities of the East continued to enjoy the privilege of issuing their own bronze coinage for local needs, and local bronze coin was interchangeable with centrally minted Roman silver at fixed rates. The common coinage and monetary system made a major contribution to cultural uniformity, and this was reinforced by the use of coin legends. Almost every coin, of whatever denomination, carried the portrait, name, and titles of a living member of the imperial family, usually the emperor himself, on one side, and an emblem, again identified by a written legend, chosen to project a significant feature of imperial ideology on the other. As a monetary system Roman imperial coinage was more extensive geographically, and lasted for a longer period, than any other in world history.
The existence of a single, empire-wide monetary system does not necessarily imply that the empire as a whole acted as a single economic unit. Between northwest Europe and the Middle East there is some evidence, although it is difficult to measure and evaluate, of distinct economic zones, which prospered or faltered according to local conditions. The Roman Empire was large and complex, and there were certainly major regional variations. However, a significant measure of economic unity was certainly created by universal mechanisms such as tax, interregional trade, and the production and consumption of goods, which the state required to provision its armies and the populations of its capital cities.
All the features of the Roman Empire which have been discussed so far are more or less identifiable on the basis of visible – indeed sometimes very conspicuous – material evidence. Other defining institutions and characteristics have to be inferred less directly. Rural settlements were much less conspicuous than the cities. To an extent the pattern of villages and other types of rural community represents the continuation of regional, vernacular traditions in areas that came under Roman control. These often preserved native traditions and styles of building, although they were open to Roman architectural influence and betray the impact of empire in other ways. Roman rule brought significant changes to the patterns of land ownership, including the growth of rural estates, and new types of land exploitation. These had a lasting impact on provincial society. The stable conditions of the empire encouraged the consolidation of landownership and a trend towards the emergence of large or middle-sized estates. This reinforced the authority of the rich in the provinces and enabled them to pass their wealth and resources, in the form of land, to their heirs. The agrarian landholdings of elite and middle-ranking families throughout the Roman provinces underpinned the flourishing life of the cities. They also helped to create a stable conservative and conformist mentality in the provincial aristocracies. The emperors themselves acquired a great deal of property, confiscated from their enemies or inherited from their would-be friends, especially in the wealthiest regions of the empire such as Spain, Italy, Africa, Asia Minor, and Egypt. Imperial estates, which were generally divided up and leased out to long-term tenants, played a large part in the supply system of the armies and the imperial capital cities. Wealthy landowners, and above all the emperors, supervised their estates through agents, who were often freed ex-slaves or members of freedmen families.
Taxation was another universal feature of the Roman Empire whose effects are almost invisible. The main exception to this generalization is in Egypt, where innumerable papyri have been recovered which document the bureaucratic workings of imperial administration, including tax collection, precisely at the point where it affected the lives of individuals. However, because our main evidence for how taxation worked comes at this hum-drum level, it is difficult to reconstruct the big picture of taxation policy. In broad terms three types of taxes may be identified. Taxes were levied on individuals and the land they owned, and the levies made on heads (capita) and on acreage (iugera) were consolidated and rationalized into a single system at the beginning of the late Roman period under Diocletian, the system of iugatio-capitatio (see pp. 64 and 181–3). The rates of the poll and land tax were fixed, not progressive, so they weighed more heavily on the poor than the rich. Taxes were also placed on the movement of goods, both at the frontiers of the empire and on provincial boundaries (portoria). Thus the growing trade and exchange of the Roman Empire yielded a significant cut for the state. Finally taxes were levied on transactions with monetary value: on inheritances, on the freeing of slaves, and on the sales of particular types of goods. Rates of payment varied to a small degree from one part of the empire to another, reflecting local traditions, but the essential precondition for Roman taxes as a whole was the existence of universal bureaucratic systems for assessing and collecting them. It was a major achievement of the Roman Empire, and one of defining characteristics that distinguished it from the barbarian kingdoms in the West, that it translated the practices of previous conquerors, who demanded tribute by right of conquest from their subjects, into permanent, institutionalized tax levies, which did more than anything to define the relationships of subjects to the political system which ruled and protected them (see pp. 469–75).8
The preceding pages have been designed to sketch in the broadest terms the social and economic conditions in the provinces under the Roman Empire. The emphasis has deliberately been placed on universal features which helped to create economic and cultural unity and can accordingly be identified as crucial defining elements of empire. It is now necessary to survey the cities and provinces of the empire on a regional basis. One purpose is to provide some idea of what the later Roman Empire looked like in material terms. Another is to identify variations within the overall pattern. The survey begins with the largest cities, whose evolution and history was directly determined by the political economy of the later empire. In the last generation most innovative work on the Roman Empire has tended to look away from the capitals to the provinces, and interpret the workings of the empire by starting at the peripheries. However, the old and new imperial capitals were by far the largest social units in the empire and in economic and social terms imposed patterns in the movement of goods which can be studied throughout and beyond the Mediterranean world.
Rome, by virtue of its name and historical traditions, was the center of the Roman world. By the time of Diocletian, Rome had long since ceased to be the main focal point of political and military power in the empire, but the Senate, “the better part of the human race” (Symmachus, Rel. VI.1), numbering some 600 members, including the richest landowning families of the western empire, retained high prestige. The senators’ public role was largely ceremonial. The old republican offices of quaestor, praetor, and suffect consul were now taken by wealthy men in the early stages of a public career, and were marked not by administrative or judicial duties but by the obligation to pay for shows and spectacles to entertain the Roman people and impress one another with their wealth and style. The practice of the late fourth and early fifth centuries is described by Olympiodorus:
Many of the Roman households received an income of 4000 pounds of gold per year from their properties, not including grain, wine and other produce which, if sold, would have amounted to one-third of the income in gold. The income of the households at Rome of the second class was 1000 or 1500 pounds of gold. When Probus, the son of Olybrius, celebrated his praetorship during the reign of the usurper John [423–5], he spent 1200 pounds of gold. Before the capture of Rome, Symmachus the orator, a senator of middling wealth, spent 2000 pounds when his son Symmachus celebrated his praetorship. Maximus, one of the wealthy men, spent 4000 pounds on his son's praetorship. The praetors celebrated their festivals for seven days. (Olympiodorus fr. 41.2, trans. Blockley)
Many members of the Senate were prodigiously wealthy, deriving their riches from land holdings in Italy and the other western provinces. They built huge villas in and around the city. Olympiodorus wrote that the great houses of Rome in his day were as large as good-sized cities, each containing its own race course, fora, temples, fountains, and various bath houses (Olympiodorus fr. 41.1). A century later Theoderic commended the wealthy Symmachus for the magnificence and good taste of his suburban villa, which “created public works of a sort in your own private dwelling,” and on the strength of this commissioned him to supervise repair work on Pompey's theater (Cassiodorus, Var. 4.51). Both passages imply the growing tendency in late antiquity for the wealthy to spend lavishly on their private properties.
Diocletian was aware of the continuing importance of the Senate, and rebuilt the Curia, its meeting place. The building still stands in the Roman forum in the form that it then took. However, the tetrarchs spent little time in the city except in November 303, when Diocletian, prematurely, arrived to celebrate the twentieth anniversary of his accession to power. It is revealing that he left the city in haste, before the year was out, unable, according to Lactantius, to tolerate the free spirit of the Roman people (Lactantius, On the Deaths of the Persecutors 17.1–2). Similar antagonism is implicit in Ammianus’ account of Constantius’ visit in 357 (Ammianus 16.10). The great cities of the empire were the only places where emperors encountered a great mass of their ordinary subjects, and these meetings were fraught with tension and significance. The tenor of an imperial reign could be defined in such moments, and the despotic Diocletian chose to avoid a confrontation with a free-speaking plebs. Lactantius, however, does not mention another initiative of Diocletian in Rome which was equally representative of an emperor's relations with the people. In 305, the year of their abdication, the tetrarchs completed the Thermae Diocletianae, a monstrous bathing complex, with almost double the capacity of the Baths of Caracalla, capable of holding 3,000 bathers at a time, dedicating the building “to their own Roman people” (ILS 646).
Diocletian himself constructed another major monument in the Forum to celebrate his vicennalia, an ensemble of five columns erected next to the temple of Concord. Four of these supported statues of the tetrarchs, and were grouped behind a central column with a statue of Jupiter. This presented the religious ideas of the tetrarchy at the center of the empire (see p. 63 and Plate 9.1). At the same time Diocletian also organized the celebration of the secular games, an event of major religious significance previously staged by the Severans in 204.
Plate 9.1 Detail from Arch of Constantine, showing Constantine delivering a speech from the rostra in the forum, addressing magistrates and military officers (© funkyfood London – Paul Williams/Alamy)
Ammianus called Rome the temple of the whole world (17.4), and implied that the Capitol remained the greatest pagan sanctuary of the empire (26.16.12), while Ausonius hailed it as the house of the gods (Ausonius XI.1). It was the symbolic center of the struggle between paganism and Christianity in the fourth century.9 Senators, like the rest of the population, were divided in their religious allegiances, but leading senators can be identified as the main champions of paganism up till the last years of the fourth century.
Between 300 and 450 only one would-be emperor resided in Rome, Maxentius, son of Maximianus, who claimed the title of Augustus between 306 and his defeat by Constantine in 312. He restored Hadrian's temple of Venus and Roma, which had been destroyed by fire, and built the huge brick basilica, which stands at the east end of the forum and must have been designed as the setting for his public appearances as judge and ruler. The basilica was later dedicated by the Senate to Constantine, and the famous colossal head of Constantine, the best known of his portraits (Plate 2.2), was found there, implying that the building continued to serve a similar function after Maxentius’ death (Aur. Victor, Caes. 40.26). As imperial visits to Rome became less frequent, the building may have been taken over as a ceremonial meeting hall and courtroom by the city prefect.10 The best comparison for this building is the equally grandiose basilica, perfectly intact today, which was constructed by Constantine at the northern Gallic capital of Trier (see p. 386 and Plate 10.5).
Constantine's most conspicuous construction in Rome was the famous arch (see pp. 168–70, Plate 5.1). More significant in the long term were his church foundations. Work began on St John Lateran in the weeks following the victory of the Milvian bridge in autumn 312. The basilica was built on the demolished foundations of the barracks that had been occupied by Maxentius’ cavalry bodyguard. Constantine's mother Helena is associated with another major basilica, the church now called S. Croce in Gerusalemme, which was attached to a palace where she now resided.11
The best known of the fourth-century Roman churches, the forerunner of the great sixteenth-century basilica on the Vatican hill, dedicated to St Peter, was not built by Constantine, but by one of his successors, probably Constans between AD 340 and 350. The site was directly superimposed on a cemetery of pagan and Christian graves, one of which was identified as a martyrion of St Peter and already served as a shrine for Christian worshippers. This was integrated into the new five-aisled building at the point where the transept and the apse intersected. The work of construction had been extremely laborious, and involved building massive substructures which effectively reversed the direction of the hill slope in order to achieve the correct orientation for the church.12 The Church of the Lateran appears to have been the seat of the bishop of Rome, but it was the tomb and basilica of St Peter, combined with its location in the greatest city of the Mediterranean, that conveyed special authority on the leaders of the Roman Church. The bishop of Rome had no lasting rivals in the western empire, and was recognized as the senior patriarch by the Council of Constantinople in 381. After the fall of the last western emperor in 476 the Pope also became effectively the senior secular authority in the western Roman Empire.
Constantius II paid a famous visit in 357, which has been immortalized in some of the best known paragraphs of Ammianus’ history, written in Rome in the 390s.
When he came to the Forum of Trajan, a creation which in my view has no like under the cope of heaven and which even the gods themselves must agree to admire, Constantius stood transfixed with astonishment, surveying the gigantic fabric around him; its grandeur defies description and can never again be approached by mortal men. So he abandoned all hope of attempting anything like it, and declared that he would and could imitate simply Trajan's horse, which stands in the middle of the court with the emperor on its back. Prince Hormisdas…remarked with oriental subtlety: “First, majesty, you must have a similar stable built, if you can. The horse you propose to fashion should have as much space to range in as this one which we can see.” (Ammianus 16.10, trans. Hamilton)
In the event Constantius marked his visit by bringing to Rome an obelisk, which had been intended for the city by his father Constantine. This was one of several that the city acquired during late antiquity (Ammianus 17.4; ILS 736).13
The city, and especially the forum, continued to be a focus for the public commemoration of emperors and senators. Senatorial wealth was used to fund public entertainments in the Circus Maximus and the Colosseum, which was restored by Theodosius I. However, secular public building on a grand scale virtually ceased after the fourth century. The material damage inflicted by Alaric's Goths in 410 was repaired, but the psychological blow had a lasting effect. We should not, however, underestimate the amount of building that must have continued in the fifth-century city. The Notitia Urbis catalogues 462 living quarters, 46,602 apartment buildings, 254 bakeries, 19 aqueducts, 11 major thermae, and 856 small bath houses. The effort required to service Rome's enormous population still dwarfed that of any other city of the empire. Looking back in the 530s, Cassiodorus reflected precisely on these conditions, which had changed by his own day:
It is evident how great was the population of the city of Rome, seeing that it was fed with supplies furnished even by far off regions, and that this imported abundance was reserved for it, while the surrounding provinces sufficed to feed only the resident strangers. For how could a people that ruled the world be small in number? For the great extent of the walls bears witness to the throngs of citizens, as do the swollen capacity of the places of entertainment, the wonderful size of the baths, and that great number of water mills which was clearly provided especially for the food supply. (Cassiodorus, Var. 11.39, trans. Barnish)
The pattern of public construction changed drastically in the fifth and sixth centuries. Virtually all new buildings were now churches, oratories, and, especially in the sixth century, monastic foundations. Fourth-century Rome contained relatively few Christian foundations. Apart from the Constantinian basilicas and the huge extra-mural church of Saint Paul on the road to Ostia, the churches were inconspicuous and made no attempt to rival pagan religious architecture. The pattern then changed. Only two major basilicas, including the present church of S. Maria Maggiore, were built in the fifth, and only one, the Church of the Holy Apostles, in the mid-sixth century, probably dedicated by Justinian's general Narses after the final defeat of the Ostrogoths in the 550s. On the other hand, parish churches during this period spread to all parts of the city and were clearly marked by external porticos and courtyards. They thus acquired the characteristic appearance of public buildings, but their distribution through the wards of the city represents a change in their social function. They served Rome's neighborhoods, as the magnetic power of the civic center began to fade.
Rome suffered another critical blow when it was attacked and plundered by the Vandals under Gaiseric in 455. The city enjoyed a revival in political terms during the third quarter of the fifth century, as it usurped the place of Ravenna as the main imperial residence in the West and became the focus of Ricimer's attempts to restore a stable western empire,14 and it benefited notably from the stability created by the Ostrogoth Theoderic's long reign from 483 to 526. Famously he visited the city in person in 500 in a manner appropriate to an emperor:
In celebration of his tricennalia he entered the palace in a triumphal procession among the people, staging circus games for the Romans. He made an annual grant to the Roman people and the poor of 120,000 modii of grain, and gave orders that each year two hundred pounds of gold should be taken from the wine tax and spent on restoring the palace or reconstructing the city walls. (Anon. Val. 2, 67)
The situation faced by Theoderic also illustrates the transformation that had overtaken the city. Much of the interior of the city was no longer inhabited, as Rome's population began to decrease. A conservative estimate puts the number of inhabitants in the fourth century at over 500,000. By the mid-sixth century the figure was not more than a tenth of this. Procopius indicates that the inhabitants and defenders were unable to man the nineteen-kilometer wall circuit during the long sieges of Rome in 537–8 and 546. Warfare and above all the plague must have hit the city hard in the 530s and 540s, but the root of Rome's decline lay in the acute diminution of its food supply, the life support system on which it had depended for over five hundred years. The city had always been supplied by a diversity of sources in Italy and overseas. Some of this was distributed without charge to free urban householders, but most was put on the market for sale at controlled prices. As in all ancient cities there was immense distress if the grain supply was interrupted, and shortages were greeted by violent rioting. The main staple, grain, was imported from Egypt, Africa, and Sicily. After the foundation of Constantinople Egyptian grain was diverted to the eastern capital, leaving Rome dependent on western sources. A critical moment came in 439 when the Vandals seized Carthage, the point of export for most of the African grain, and used their sea power to menace shipping out of Sicily. The vital change was not a direct embargo on exports from Carthage. There is no evidence that the Vandals, who set up a highly effective state in their new African environment, wished to curtail normal economic activity, but they were able to use their control of Carthage and their maritime strength as powerful bargaining weapons in dealing with the western empire. Moreover they cut off the African tax revenues, in kind as well as cash, to Rome. The loss of the African annona, combined with growing insecurity in the Mediterranean, will have driven up prices as it reduced Rome's supply. The situation was naturally compounded with the final fall of the western empire in 476. The ability of the city of Rome to feed its enormous population in earlier centuries had depended directly on its role as an imperial city which could impose tax demands on its subjects. Now it had to pay for what it consumed. The population accordingly shrunk to a level much closer to that of other larger cities of the later empire.15