With the death of Alexander the empire enters one of its most troubled and ill-recorded periods. The literary sources are inadequate, often no more than extracts from vanished histories put together by later Byzantine scholars, and offer little detail of a period of major instability with a pattern of attacks from both the German tribes and the Sasanian Persians over fifty years (234-84). Something can be learned from the study of coin hoards (the assumption being that they were hidden at times of trouble and can be roughly dated by the year of the latest coin), destruction levels, and the building of fortifications or the walls of cities, but the sequence of events is still unclear.
There were at least eighteen emperors in these years who could lay some claim to legitimacy. Their average reign was only two and a half years. It is not difficult to find the reasons for this high turnover. The geographical extent of the attacks on the empire ensured there were several armies campaigning at any one time. Their commanders might chance their luck at seizing power or even proclaim themselves emperor to make themselves more respected as leaders. The armies themselves had every incentive to declare their commanders emperor in the hope that this would give them access to greater plunder. There were also power struggles within the armies between rival commanders and several emperors died at the hands of their own men. Others died fighting invaders.
In fact, the crisis of the third century was as much an internal as an external one. It showed up the inherent vulnerability of the imperial system at a time of military stress. As many resources were used by the emperors fighting rivals as in confronting invading enemies. The determination needed to survive and the priority given to fighting alienated the usurping generals from the leisured senatorial classes and from the Romanplebs who resented resources being diverted to the troops. The toughness and resolution of the emperors are vividly portrayed in their portrait busts. They are among the more impressive achievements of Roman sculpture. As examples one might pinpoint the bust of Philip the Arab (emperor 244-9) in the Vatican Museums or the head of Trajan Decius (emperor 249-51) in the Capitoline Museums in Rome.
Attacks by German tribes were renewed in the 230s but they were relatively small scale and tackled with some ease by the new emperor Maximinus, a rugged outsider from Thrace. The real threat to Maximinus came from Rome where there were still Severan supporters in the senate. They exploited a revolt in Africa against taxation led by a local governor, Gordian, and eventually proclaimed his grandson, also Gordian, as Caesar. Maximinus rushed south to deal with the situation but drove his men so harshly that they mutinied and killed him in 238. The Gordian grandson, though still only a boy, emerged as sole emperor in the same year (as Gordian III).
Inevitably Gordian relied heavily on strong military men of whom the most prominent was an Anatolian, Timesitheus. While raids on the empire continued along the Danube border, more threatening was a series of attacks by the Sasanians on Roman border towns masterminded by the new Sasanian king, Shapur. They provoked a major Roman counter-attack by Gordian in 243. Gordian may have been defeated—he certainly withdrew for some reason to northern Mesopotamia and it was here that his frustrated men murdered him in early 244. The Praetorian Prefect, Philip the Arab, was hastily declared the new emperor and had to hurry back to Rome to secure his position after having paid a large ransom to the Persians. He took Gordian’s body to Rome with him, claiming that the young emperor had died of disease and deserved to be deified. This was a major cover-up, not only of the truth behind Gordian’s death but of the probable defeat that had led to it.
After Philip had paid out the ransom, glorified his Syrian home city Chahba, now renamed Philippopolis, and flattered Rome by celebrating a thousand years since its foundation, he was short of money. He withdrew subsidies to the northern tribes and this led to uprisings along the Danube. It is now that there are the first rather obscure mentions of a group called the Goths. Once again the unresolved issues of the succession came to the fore. The emperor had to delegate commands but this simply created more power hungry generals. One of these was Decius, from the province of Illyricum on the Danube, who had already had a distinguished career as consul, provincial governor, and prefect of Rome. He was now ordered to suppress a revolt in one of the legions and his success led to him being declared emperor by his troops. Philip, who had little military experience, died confronting him (249).
Decius attempted to enforce some form of uniformity on the empire by requiring that all offer a sacrifice to the ‘ancestral gods’ of the empire and consume the sacrificial food and drink. This was hardly an onerous demand and most subjects of the empire must have accepted this ritual act without hesitation. Participants seem to have been given considerable leeway in interpreting ‘god’ or ‘gods’ in the way they wished. As there were accurate census lists, participants could be checked out and given a certificate when they had complied. Although there is no evidence that Christians were Decius’ target, the campaign left them with a problem of conscience. Some complied in the sacrifices, some bought their certificates, and others openly, even joyfully, refused to sacrifice, in effect leaving them open to persecution (see further pp. 595-7). Despite his experience as an administrator, Decius was never a successful commander and he died, in his turn, in 251 fighting off an invasion of the Goths and others that appears to have penetrated well into the empire. Thousands of trained men may have disappeared with him in poorly recorded defeats.
The immediate effect of Decius’ death was confusion. The Persians were rampaging through Syria in 252, possibly with some collaboration from discontented Syrians who were realizing that the empire could no longer give them protection. Even Antioch, one of the great cities of the eastern empire, was sacked. Local communities were beginning to accept that they must defend themselves, either through building fortifications or raising their own troops. The emperor could not be everywhere but there was no effective way of delegating commands without the risk of a challenge from any general winning a victory.
From 253 power at the centre was shared by a new emperor Valerian and his son Gallienus. Valerian was of the old school, a conservative aristocrat from Italy. He was already in his sixties but he was soon on the move. His priority was to stem the advances of the Sasanians, which he did temporarily, but he then headed to the German borders and then back to the east. Gallienus, meanwhile, was sent to keep order on the Rhine.
Valerian was obsessed with the unity of the empire and he issued another edict requiring sacrifices to the gods. Unlike Decius he targeted Christians, especially bishops, many of whom were executed. Yet his own reign ended in disaster in 260 when he was seized during negotiations with Shapur. Shapur humbled the proud Valerian by using him as a footstool from which to mount his horse and he eventually died in captivity. The Sasanian triumph was trumpeted by Shapur in a magnificent series of rock reliefs. The king humiliates his Roman enemies from times past. Gordian is shown being trampled underfoot by Shapur’s horse. Philip pleads before the king for his release. Valerian, on foot, is held by his wrist by his conqueror.
The 250s and 260s were a time of almost continual unrest as invasions struck ever deeper within the empire. In 260 the Alamanni reached as far south as Milan (the Roman Mediolanum) before they were defeated by Gallienus. (It was probably now that the importance of Milan and the inadequacy of Rome as a base for the defence of Italy first became apparent.) In 259-60 other German tribes devastated eastern Gaul and made their way down to the Mediterranean. Some bands even penetrated Spain and Mauretania. In 267 the Heruli, a people not recorded on any other occa-sion—a reminder, in fact, of how transient many of these raiding groups were— took an invasion fleet of 500 ships into Greece and sacked Athens. The great Odeion of Agrippa and the Hellenistic stoas were destroyed and the survivors had to hurriedly construct a new wall for the city from the debris (parts of which can still be seen). Athens never fully recovered from the attack.
Gallienus was a man of enormous energy. Despite the range of attacks he managed to maintain peace in the central part of the empire for some six or seven years in the 260s. He had the good sense to maintain close links with Egypt and north Africa so that there would always be supplies of food. He was also aware of how counter-productive it was to persecute Christians, so freedom of their worship was now respected. One of his military innovations was a specialized cavalry force which, combined with infantry, could be moved more quickly than the legions to deal with emergencies. By now senators had virtually disappeared from commands—talent had to come before birth.
Crucially, Gallienus also understood that the empire might be better defended by dividing the imperial command. The prompt came from one of his commanders on the Rhine frontier, Postumus, who was declared emperor by his troops in 260. Pos-tumus soon found himself in control along the northern frontier, with a ‘capital’ at Trier, and with influence as far south as the Alpine passes. The next step, and that taken traditionally by usurpers, would have been to march towards Italy to challenge Gallienus, but Postumus hesitated. He may have been wanting to consolidate his position in the west before he moved and he did go on to win over the legions of Britain and Spain. However, even then he did not march and he seems to have been happy with a ‘Gallic empire, which he ran as if it was a Roman state. It is probable that his rule depended not just on the legions but on the support of the local aristocracy, whose main concern would have been the defence of their estates. They may have offered him the taxation he needed to survive on condition he remained there to defend them. In fact Postumus campaigned so successfully against the Germans that between 263 and 271 they gave no more trouble. Although Postumus’ ‘empire’ was an affront to the centralized traditions of the empire, it provided a model to follow. Gallienus, in fact, realized the advantages of the arrangement and left Postumus alone until 265 when he tried unsuccessfully to defeat him. When Gallienus was murdered, his successor Claudius II (268-70) also tolerated Postumus and his successors. The ‘Gallic empire’ survived until 274 when it was reconquered by a later emperor, Aurelian (ruled 270-5).
Another area of the empire to achieve independence during this period was Palmyra. This cosmopolitan trading city on the eastern border of the empire, its ruins still among the most haunting of the empire, had been incorporated into the province of Syria in ad 18 but its ruling families, who depended on trade with the east, had always preserved its separate identity. Its king, Odaenath, successfully harried the Sasanians as they retreated from the campaign of 260 and Gallienus was prepared to allow him to coordinate the defence of the east. Gallienus clearly regarded this as an official appointment, a form of senior governorship within the Roman system, but Odaenath then declared himself ‘King of Kings, on the Persian model, elevated his son Vaballathus as successor, and held sway over much of Syria, Palestine, and Mesopotamia. Under his redoubtable widow Zenobia, who had probably murdered him in 268, the ‘empire’ annexed Egypt and much of Asia Minor. This was the largest ‘Greek’ kingdom known since the days of the Hellenistic monarchies. Zenobia appears to have seen herself as a new Cleopatra but she fared no better at the hands of the Romans. When she declared Vaballathus, still a boy, to be an Augustus in 271 the Romans moved to crush her. City after city rallied back to the empire as Zenobia’s military weakness was exposed. Palmyra was regained for the empire in 273 although Zenobia survived Aurelian’s triumph in Rome and settled down to what appears to have been a respectable life as the wife of a Roman noble to whom she bore children. It is a pity that so little is known of this redoubtable woman.
World History
