In 441 AD the realm of Theodosius was in danger from a powerful combination. It was involved in war with three powers, the Huns, Vandals, and Persians, at the same time, and at least two of them, the Huns and Vandals, were in league. The rise of the great Hunnic power, which threatened European civilization in the fifth century, was as sudden and rapid as its fall. The Huns had gradually advanced from their Caucasian abodes, pressing westward the Goths who lined the north shores of the Black Sea, and had now become a great power. Attila, their king, ruled over a European empire stretching from the Don to Pannonia, and including many barbarian kingdoms. In 395 Asia Minor and Syria had been ravaged by Huns entering by the north-east passes, but in 400 we find Uldes, a king of other Huns, hovering on the shores of the Danube and putting Gainas to death. At the beginning of Theodosius’ reign the Romans gained a victory over this Uldes, and followed up the success by defensive precautions. The strong cities in Illyricum were fortified, and new walls were built to protect Byzantium; the fleet on the Danube was increased and improved. But a payment of money was a more effectual barrier against the barbarians than walls, and about 424 Theodosius consented to pay 350 lbs. of gold to Rugila or Rua, king of the Huns, who had established himself in the land which is now Hungary, and to whom, about 433, the western government conceded a part of Pannonia. It was to Eugila probably, that Aetius, afterwards to be the terror of Huns, was sent as a hostage; and it was he who supplied Aetius with the auxiliaries for the support of the tyrant John. When Eugila died in 434 his nephews Attila and Bleda, the sons of Mundiuch, succeeded him, and a new treaty was contracted by which the payment was doubled.

Attila cherished friendly relations with Aetius, the general of Valentinian, and entered into an alliance with Gaiseric, king of the Vandals, who had passed from Spain into Africa in 429 and established themselves there, as will be related in another chapter. The movements of Attila from 434 to 441 are lost to us, but at the latter date we find him ruler over an enormous barbaric empire in central Europe, which stretched to the Caucasian mountains on the east, threatening the provinces of Theodosius. At the same time the forces of the East were required against the Vandals and the Persians; and it has been suspected that the hostilities of the latter were not un­influenced by the Huns, as the hostilities of Attila were certainly influenced by the movements of Gaiseric.

The Vandals were unique among the German nations by the fact that they maintained a fleet, so that they were able to afflict the eastern as well as the western lands of the Mediter­ranean, and to make piratical raids on the coasts of Greece; it was even thought advisable to fortify the shore and harbours of Constantinople against a possible Vandal expedition. The security of traders and commercial interests demanded that an attempt should be made to suppress this evil, and a large armament, whose numbers have perhaps been exaggerated, was fitted out by Theodosius, and placed under the command of Areobindus. It was despatched to Sicily to operate against Gaiseric, who had taken Lilybaeum and was besieging Panormus; but tidings of some dark danger which threatened him in Africa induced the friend of pirates to make a truce with the Roman general and hurry back to his kingdom. The danger came from a son-in-law of Boniface, the famous Sebastian, who died as a martyr and became a favourite subject with Italian painters; but how his passage into Mauretania, of which Prosper tells us, menaced Gaiseric is not clear. From a fragment, attributed to John of Antioch and preserved by Suidas, it would seem that he was the commander of a pirate crew which served the Emperor Theodosius; and so we might suspect that his invasion of Mauretania was closely connected with the Sicilian expedition.

Most of the military forces which had not accompanied Areobindus to the West accompanied Anatolius and Aspar to the East. What happened there is not recorded clearly, but the hostilities were of short duration and slight importance.

At this moment Attila determined to invade the Empire. It was destined that he, like Alaric the Visigoth at an earlier, and Theodoric the Ostrogoth at a later time, should desolate the provinces of the East before he turned to the West. He condescended to allege a cause for his invasion; he complained of the irregular payment of tribute, and that deserters had not been restored; but the government at Constantinople disregarded his embassy. Then Attila, who had advanced towards the Danube from his home, which was somewhere on the Theiss, laid siege to the city of Ratiaria, an important town on the Ister in Dacia ripensis. Here ambassadors arrived from New Rome to remonstrate with the Huns for breaking the peace, and the invader replied to their complaints by alleging that the bishop of Margus had entered Hunnic territory and robbed treasures from the tombs of their kings; the surrender of these treasures and of deserters was demanded as the condition  of peace.

The   negotiations   were  futile, and, having captured Ratiaria, the Hunnic horsemen rode up the course of the Ister and took the great towns which are situated on its banks. Viminacium and Singidunurn, in Upper Moesia, were overwhelmed in the onslaught of the "Scythian shepherds," and it seems that the friendship of Attila with Aetius did not preserve the town of Sirmium in Lower Pannonia from being stormed. The town of Margus, which faces Constantia on the opposite side of the river, fell by treachery; the same bishop whom Attila accused of robbing tombs incurred the eternal disgrace of betraying a Roman town and its Christian inhabitants to the greed and cruelty of the heathen destroyer. The invaders advanced up the valley of the Margus, now called the Morawa, and halted before the walls of Naissus, now called Nisch, in the province of Dardania—the city which had been strengthened and improved by the affection of the great Constantine, and which had recently given to the Empire a Third Constantius. The inhabitants made a brave defence, but the place fell before the machines of Attila and the missiles of a countless host. Then the victors passed south-eastward through narrow denies into Thrace and penetrated to the neighbourhood of Constantinople. Attila was not to lay siege to New Rome, just as ten years later when he invaded Italy he was not to lay siege to Old Rome; but he took Philippopolis and Arcadiopolis, and a fort named Athyras, not far from the Bosphorus.

If the nameless bishop of Margus is branded with infamy for his recreant Hunnism, the name of the strong fortress of Asemus in Lower Moesia deserves to be handed down by history in golden letters for its brave and successful resistance to the Hun, even as the town of Plataea earned an eternal fame by its noble action in the Persian war. While the great towns like Naissus and Singidunum yielded to the violence of the whirlwind, Asemus did not bend. A division of the Huns, different from that which marched to Thrace, but of countless multitude, invaded Lower Moesia and laid siege to Asemus. The garrison not only defied the foes, but so effectually harassed them by sallying forth that they retreated. The Asemuntians were not satisfied with a successful defence. Their scouts discovered the opportune times, when plundering bodies of the Hunnic army were returning to the camp with spoils, and these moments were eagerly seized by the adventurous citizens; the pillagers were unexpectedly attacked; many Scythians were slain, and many Roman prisoners, destined to languish in the wilds of Hungary, were rescued from captivity.

Meanwhile the Roman armies were returning from their campaigns in the East and in the West, but it is not clear whether the troops were actually employed against Attila, or whether Areobindus, who had commanded against Gaiseric, or Aspar, who had commanded against Isdigerd (Yezdegerd), the Persian king, accomplished anything of note against the Huns. A battle was certainly fought in the Thracian Chersonese, and Attila won the victory; but we know not who was his opponent. Nor do we know what the master of soldiers in Thrace, Theodulus by name, was doing at Odessus. After this battle a peace was concluded between Theodosius and Attila. As it was Anatolius who was the negotiator, it was generally known as the "Peace of Anatolius" (443 D) . The terms were that the former payment of 700 lbs. of gold, made by the Romans to the Huns, was to be trebled; besides this 6000 lbs. of gold were to be paid at once; all Hunnic deserters were to be restored, while Roman deserters were only to be given up for a payment of 10 solidi a head.

For four years after this the Illyrian and Balkan lands were not laid waste by the harryings of the great enemy, but in 447 Scythia and Lower Moesia, which had suffered less in the former invasion, felt the presence of the Hun again. Marcianopolis was taken, and the Roman general Arnegisclus fell in a battle fought on the banks of the river Utus. At the same time another multitude descended the valley of the Vardar and advanced southward—though some doubt the record—as far as Thermopylae.

Meanwhile embassies passed to and fro between the court of Attila and the court of Theodosius; and of the embassy of Maximin the historian Priscus, who accompanied the am­bassador, has left us copious and interesting details, which give us a glimpse of Hun life, and will be reproduced in another chapter.

Until the end of the reign of Theodosius the oppressive Hun-money was paid to Attila; but when Marcian came to the throne he refused to pay the stipulated tribute. It seemed that the Illyrian peninsula would be again trampled under the horse-hoofs of Hunnic cavalry; but complications in the West averted the course of the destroyer in that direction, and the realm of Valentinian, not the realm of Marcian, was to resist the storm.

The Hunnic empire had assumed a really formidable size and power under the ambitious warrior Attila, who, we are told, in spite of his hideous features and complexion, had the unmistakable aspect of a ruler of men. Gepids and Ostro­goths, with many other German tribes, acknowledged the over-lordship of the king of the Huns, who, as Jordanes says, "possessed Scythian and German kingdoms"—Scythica et Germanica regna possedit—though the extent of his domination is often exaggerated. Before 440 the Huns had attempted an invasion of Persia, and Roman officers talked of the chances of the overthrow of the Persian power by Attila and the possible consequences of such an event for the Roman world. But it was not destined that Attila should attempt to confront the great power of Asia; he was to shatter his strength in a contest with the forces of Europe on one of the great battlefields of the world's history.