One of the strangest facts in history is the rapid decline of Roman power that set in immediately after the Empire had enjoyed such a succession of good rulers as had never before fallen to its lot. The period of eighty-four years which began with the accession of Nerva and ended with the death of Marcus Aurelius has always been regarded, and rightly regarded, as the golden age of Rome. Trajan was, it is true, a warlike Emperor by choice, and Marcus Aurelius the same by necessity, but Rome had never had since its founding any but the briefest intervals of peace. War, in short, was its natural condition, and it had seldom been carried on with more success than it was by Trajan in Dacia and by Aurelius against the Quadi and the Marcomanni. On the other hand, the reigns of Hadrian and Antoninus Pius 117—161) made up together forty-four years, considerably more than what is usually reckoned as a generation, of almost unbroken peace. Yet the good effects of nearly a century of wise rule seemed to vanish almost immediately when the last of the "Good Emperors" passed away. It is true that Aurelius had a deplorably weak and vicious successor. But Commodus was not more contemptible than Caligula, Nero, or Domitian, and Rome had survived their rule without much apparent injury. Some writers have found a cause in a succession of plagues which raged throughout the Empire with an almost unexampled severity, and it is true that the century which followed the year 165 was terribly distinguished by this visitation, but no external calamities are sufficient to account for a nation's decay. These causes are to be sought elsewhere, within rather than without, in the life of men more than in the calamities which years of famine or of pestilence inflict upon them. And it is clearly beyond my province to do more than indicate them in the very briefest way. We see signs of what was going on in days when to all appearance the Empire was most flourishing, while it was certainly still pursuing its career of conquest. Virgil writes a great poem to commend the honest healthy toil of a country life to a generation which had ceased to care for it. The cities were more and more crowded, for the luxuries which they put within the reach of even the poorest were more and more sought after, but the country was passing into a desert or a pleasure ground. The farmers or peasants who had formed the backbone of Roman armies had ceased to be; their fields, where they had not gone out of cultivation, were tilled by huge gangs of slaves. Provincial towns which in old days had been strong enough to make treaties on equal terms with Rome were now half in ruins, with a scanty population that barely contrived to exist. With every year things grew worse and worse. And the Empire aggravated the evils which at first it had done much to palliate if not to remedy. It had superseded the Republic, because this had become utterly corrupt; but in time it became as corrupt itself, and for the corruption of a despotism there is no cure. A succession of able rulers put off the end for a time, but it had to come. And when it came there came with it more vigorous races out of whom was to be formed by degrees, not without help of the old order which they swept away, a new civilisation.
Commodus, the unworthy son and successor of the good Aurelius, reigned but for a short time. He was assassinated in his thirty-second year. With his death began, it may be said, the rule of the sword. His successor, indeed, Pertinax by name, was chosen by the Senate, and well deserved his election, but he reigned for something less than ninety days, and the Praetorians, the soldiers of the capital, murdered him and sold the throne openly to the highest bidder. To this arrogance the legions in the provinces refused to submit. The principal armies put up candidates of their own. We need not follow the succession of these short-lived rulers. It will suffice to say that in the hundred and five years which intervened between the death of Aurelius and the accession of Diocletian (180–285) there were no less than twenty Emperors, not to mention innumerable Pretenders—it was said that at one time thirty claimed the throne.
For a time the spectacle of the Roman armies engaged in almost incessant struggles with each other does not seem to have produced the effect which might have been expected on the tribes outside the frontiers of the Empire. No movement of any importance among the barbarians is recorded during the fifty years which followed the murder of Pertinax by the Praetorians. In 209, indeed, the Britons of the north attacked the Roman province, and were punished, without any lasting effect, by Septimius Severus. But the event was of no particular importance, for the North Britons were not powerful enough, even if they had succeeded, to seriously affect the course of events. Causes with which we are not exactly acquainted kept the far more formidable tribes of Germany inactive. We hear of a combination among them in the reign of Aurelius which might well have become dangerous, if, to use the language of Gibbon, it included all the nations from the mouth of the Rhine to the mouth of the Danube. But it came to nothing. The tribes which first took the field were defeated. Discouragement and dissension kept the others inactive. Dissension, indeed, was the most potent influence which worked in favour of the Romans. In his remarkable treatise on Germany and its tribes Tacitus gives a description of the people which emphasizes their superiority in many important respects to the degenerate sons of Rome. But he speaks with satisfaction of the internal strife which prevented them from becoming formidable, mentioning one great conflict in which one tribe had been wholly destroyed by its neighbours, and adds, "While the destinies of Empire hurry us on, fortune can give us no greater boon than discord among our foes."
But this state of things naturally would not last. It would cease when some chief of commanding ability and strong personal influence should come to the front, or when some tribe should become so powerful as to attract or compel its neighbours to unite with it. Such a tribe came upon the scene later on in the first half of the third century of our era. The Gothi, to use the most common of the various forms of their name, are first mentioned many centuries before the time of which I am now speaking. Pytheas, of Marseilles, who travelled in Northern Europe about the time of Alexander the Great, speaks of them as inhabiting the coasts of the Baltic, and Tacitus, writing about 90 a.d. , locates them in much the same district. A hundred years or so after this date, however, they are spoken of as dwelling near the Black Sea. We need not trouble ourselves, however, with their place of abode, nor yet with the question of their race. Some writers hold that they were of the Slavonic family, not the Teutonic. That there were some Slavs in the great multitude which the Romans knew by the common name of Goths is more than probable. In just the same way there was a Celtic element in the great Teutonic swarm which had so nearly overrun Italy at the close of the second century B.C. But all that we know about them, whether as regards their habits or their appearance, would lead us to think that they were Germans.
Some time, therefore, about 247 a.d. , the Goths invaded and overran the province of Dacia. Crossing the Danube into Maesia (Bulgaria) they besieged its capital town, now known by the name of Pravadi (twenty-five miles to the west of Varna). The town was ill-protected, for with the whole province of Dacia between it and the frontier of the Empire it anticipated no danger. The inhabitants saw nothing better to do than to buy off the enemy by the payment of a large ransom. Such a policy is seldom successful, as we know from the history of our own island, where the plan of buying off the Danes was tried again and again to very little purpose. The Goths departed, and before long came back again.
Decius, who had by this time supplanted Philip the Arabian on the imperial throne, on receiving the news of this second invasion, marched to the relief of the provinces attacked. He found the barbarians besieging Nicopoli (on the southern bank of the Danube). On his approach they promptly raised the siege, marched across Maesia and made their way over the Balkans with the intention of attacking Philippopolis. Decius followed them, without apparently taking due precautions against surprise, for the Goths turned upon him, and routed his army. His forces were so shattered that he could not attempt to help Philippopolis, which not very long afterwards was taken by storm and sacked.
Decius, though he had made a disastrous mistake, was a brave and capable soldier. He took prompt measures to retrieve his defeat, guarding the places where the Danube could be crossed and the Balkan passes so as to prevent reinforcements from reaching the Goths. These, on their part, had suffered severely. The siege and storms had cost them many lives; their supplies were running short, for they carried no stores with them, and could draw but little sustenance from a country which they had wasted. And they were much alarmed at the prospect of having their retreat cut off. Under these circumstances they offered to surrender all their booty and all their prisoners, if they were permitted to return unharmed to their own country. Decius refused to accept the offer. He probably thought, and had some reason for thinking, that no agreement could be profitably made with barbarians. The only way to deal with the Goths was to deal with them as Marius had dealt with the Cimbri and Teutones. The invaders prepared to fight. The battle that followed was obstinately contested. The Goths were drawn up in three lines—we may observe from the first indications of a certain military skill and training in the tribe—the third of which was protected by a morass. The first and the second of these were broken; the third stood firm, and repulsed all the attacks of the legions. The Emperor's son had fallen early in the day; of the fate of Decius himself nothing was ever known. What is certain is that the army was almost annihilated. The Goths were able to make their way home without losing their spoil or their prisoners. They even received a great sum for promising not to molest again the provinces of Rome, till, of course—for such must have been the proviso understood on both sides—they should find it convenient to do so. This battle lacks a name, for the place where it was fought cannot be identified, but it was an event of the greatest importance. Rome had suffered worse disasters before, but never one that entailed so great a loss of credit. A barbarian army destroys a provincial capital, defeats two armies, slays the Emperor himself, and returns home, not only with all its booty, but with a heavy bribe with which its forbearance had been purchased. Clearly this was the beginning of the end.
For some years after their campaigns in the region of the Danube, the Goths occupied themselves with expeditions which bear a curious resemblance to those made by their kinsmen of later times, the Vikings and Northmen. They do not seem to have had any seamanship of their own, but they lured or compelled the maritime population of the Black Sea coast-line to assist them. Their first voyage was eastward. They sailed along the northern coast of the Black Sea, taking Pitsunda on their way, rounded the eastern end, and finally captured Trebizond, the wealthiest city in northern Asia Minor, where they possessed themselves of a vast quantity of spoil and a multitude of prisoners. Their next voyage had a westerly direction. They overran the province of Bithynia. The famous towns of Nicaea and Nicomedia, among others, fell into their hands, almost without any attempt at resistance. It was more than three centuries since these regions had known the presence of a foreign enemy. They had no troops of their own, except, possibly, some local levies which certainly had had no experience of warfare, and the legions which should have defended them had sadly degenerated both in courage and in discipline. The third expedition of the Goths took them outside the Black Sea into the Ægean. Their fleet sailed into the Piraeus. Athens, which had not attempted, possibly had not been permitted, to repair its walls, demolished more than three hundred years before by Sulla, was taken and plundered. Greece could offer no resistance. It had neither means nor men. The invaders still advanced westwards, and threatened Italy itself. Here, however, their progress was stayed. But from this expedition also, audacious as it was, they returned in safety. It gave another proof, not less significant than the death of Decius, how low the Empire had already fallen.
While the Goths were invading the south-eastern provinces of the Empire, other enemies were busy in the north and west. The Franks now make their first appearance in history. The name which meets us frequently in the modern world, notably in France, and in such terms as Franconia, Frankfort, Frankenthal, means the "free," and probably originated in a combination of the tribes who inhabited the eastern bank of the Rhine, and who assumed this title by way of distinguishing themselves from the subjects of Rome on the opposite side of the river. The Franks laid waste the province of Gaul, crossed the Pyrenees and desolated Spain. We know very little of the details of their invasion. One of the so-called "Thirty Tyrants," Postumus by name, is said to have checked their progress, and done something to protect the Roman provinces of the West. Postumus was slain in 267 a.d.
This date belongs to the period of extreme depression which coincides with the reigns of Valerian and Gallienus. Valerian was a favourite lieutenant of the Emperor Decius, and seems to have been a man of high character and ability. But circumstances were too strong for him. Great as were the dangers that threatened the European provinces of the Empire, it was on the Asiatic frontier that he found his presence more imperatively demanded. A revolution in Parthia had restored the ancient dynasty of the Persian kings, or, at least, a family that claimed that character. The new line of kings was now represented by a certain Shapar, or, as the Romans spelt it, Sapor. Armenia, long a bone of contention between Rome and Parthia, was overrun; the garrisons on the Euphrates were forced to surrender. Valerian hastened to meet the new enemy, encountered him near Edessa, and suffered a crushing defeat. We know next to nothing of what happened except that the legions were led, by the folly of their chief or the treachery of those whom he trusted, into a hopeless situation; that their attempt to cut their way through the hosts of the enemy was repulsed with great loss; and that in the end Valerian had to surrender himself to Sapor, and that the legions laid down their arms. There was nothing now to stop the Parthian king. The splendid city of Antioch was taken and plundered or burnt. He even crossed the Taurus range, and captured the wealthy city of Tarsus. It is impossible to say where he would have stopped, had it not been for the courage and ability of Odenatus, the governor of Palmyra and his wife Zenobia. It was they, not the Roman arms that compelled the Parthians to make their way back to their own country.
Valerian was never released from captivity. Stories—whether true or no it is impossible to say—were told of the humiliations to which he was subjected by the Persian king. Whenever Sapor mounted his horse, he used to put his foot on the neck of his captive. And when the unhappy man was released by death, his skin was stuffed with straw, and the figure preserved in one of the Persian temples, "a more real monument of triumph," remarks Gibbon, "than the fancied trophies of brass and marble so often erected by Roman vanity." Whatever may be the truth about this or that fact, it is certain that this period witnessed the infliction of two unprecedented humiliations on the dignity of Rome, one Emperor slain in battle, another kept in a dishonourable captivity.