The Balkan Peninsula in Classical Times 400 B.C. - A.D. 500.
In the earlier historical times the whole of the eastern part of the Balkan peninsula between the Danube and the Aegean was known as Thracia, while the western part (north of the forty-first degree of latitude) was termed Illyricum; the lower basin of the river Vardar (the classical Axius) was called Macedonia. A number of the tribal and personal names of the early Illyrians and Thracians have been preserved. Philip of Macedonia subdued Thrace in the fourth century B.C. and in 342 founded the city of Philippopolis. Alexander's first campaign was devoted to securing control of the peninsula, but during the Third century B.C. Thrace was invaded from the north and laid waste by the Celts, who had already visited Illyria. The Celts vanished by the end of that century, leaving a few place-names to mark their passage. The city of Belgrade was known until the seventh century A.D. by its Celtic name of Singidunum. Naissus, the modern Nish, is also possibly of Celtic origin. It was towards 230 B.C. that Rome came into contact with Illyricum, owing to the piratical proclivities of its inhabitants, but for a long time it only controlled the Dalmatian coast, so called after the Delmati or Dalmati, an Illyrian tribe. The reason for this was the formidable character of the mountains of Illyria, which run in several parallel and almost unbroken lines the whole length of the shore of the Adriatic and have always formed an effective barrier to invasion from the west. The interior was only very gradually subdued by the Romans after Macedonia had been occupied by them in 146 B.C. Throughout the first century B.C. conflicts raged with varying fortune between the invaders and all the native races living between the Adriatic and the Danube. They were attacked both from Aquileia in the north and from Macedonia in the south, but it was not till the early years of our era that the Danube became the frontier of the Roman Empire. In the year A.D. 6 Moesia, which included a large part of the modern kingdom of Serbia and the northern half of that of Bulgaria between the Danube and the Balkan range (the classical Haemus), became an imperial province, and twenty years later Thrace, the country between the Balkan range and the Aegean, was incorporated in the empire, and was made a province by the Emperor Claudius in A.D. 46. The province of Illyricum or Dalmatia stretched between the Save and the Adriatic, and Pannonia lay between the Danube and the Save. In 107 A.D. the Emperor Trajan conquered the Dacians beyond the lower Danube, and organized a province of Dacia out of territory roughly equivalent to the modern Wallachia and Transylvania, This trans-Danubian territory did not remain attached to the empire for more than a hundred and fifty years; but within the river line a vast belt of country, stretching from the head of the Adriatic to the mouths of the Danube on the Black Sea, was Romanized through and through. The Emperor Trajan has been called the Charlemagne of the Balkan peninsula; all remains are attributed to him (he was nicknamed the Wallflower by Constantine the Great), and his reign marked the zenith of Roman power in this part of the world. The Balkan peninsula enjoyed the benefits of Roman civilization for three centuries, from the first to the fourth, but from the second century onwards the attitude of the Romans was defensive rather than offensive. The war against the Marcomanni under the Emperor Marcus Aurelius, in the second half of this century, was the turning-point. Rome was still victorious, but no territory was added to the empire. The third century saw the southward movement of the Germanic peoples, who took the place of the Celts. The Goths invaded the peninsula, and in 251 the Emperor Decius was killed in battle against them near Odessus on the Black Sea (the modern Varna). The Goths reached the outskirts of Thessalonica (Salonika), but were defeated by the Emperor Claudius at Naissus (Nish) in 269; shortly afterwards, however, the Emperor Aurelian had definitively to relinquish Dacia to them. The Emperor Diocletian, a native of Dalmatia, who reigned from 284 to 305, carried out a redistribution of the imperial provinces. Pannonia and western Illyria, or Dalmatia, were assigned to the prefecture of Italy, Thrace to that of the Orient, while the whole centre of the peninsula, from the Danube to the Peloponnese, constituted the prefecture of Illyria, with Thessalonica as capital. The territory to the north of the Danube having been lost, what is now western Bulgaria was renamed Dacia, while Moesia, the modern kingdom of Serbia, was made very much smaller. Praevalis, or the southern part of Dalmatia, approximately the modern Montenegro and Albania, was detached from that province and added to the prefecture of Illyria. In this way the boundary between the province of Dalmatia and the Balkan peninsula proper ran from near the lake of Scutari in the south to the river Drinus (the modern Drina), whose course it followed till the Save was reached in the north. An event of far-reaching importance in the following century was the elevation by Constantine the Great of the Greek colony of Byzantium into the imperial city of Constantinople in 325. This century also witnessed the arrival of the Huns in Europe from Asia. They overwhelmed the Ostrogoths, between the Dnieper and the Dniester, in 375, and the Visigoths, settled in Transylvania and the modern Rumania, moved southwards in sympathy with this event. The Emperor Valens lost his life fighting against these Goths in 378 at the great battle of Adrianople (a city established in Thrace by the Emperor Hadrian in the second century). His successor, the Emperor Theodosius, placated them with gifts and made them guardians of the northern frontier, but at his death, in 395, they overran and devastated the entire peninsula, after which they proceeded to Italy. After the death of the Emperor Theodosius the empire was divided, never to be joined into one whole again. The dividing line followed that, already mentioned, which separated the prefecture of Italy from those of Illyria and the Orient, that is to say, it began in the south, on the shore of the Adriatic near the Bocche di Cattaro, and went due north along the valley of the Drina till the confluence of that river with the Save. It will be seen that this division had consequences which have lasted to the present day. Generally speaking, the Western Empire was Latin in language and character, while the Eastern was Greek, though owing to the importance of the Danubian provinces to Rome from the military point of view, and the lively intercourse maintained between them, Latin influence in them was for a long time stronger than Greek. Its extent is proved by the fact that the people of modern Rumania are partly, and their language very largely, defended from those of the legions and colonies of the Emperor Trajan. Latin influence, shipping, colonization, and art were always supreme on the eastern shores of the Adriatic, just as were those of Greece on the shores of the Black Sea. The Albanians even, descendants of the ancient Illyrians, were affected by the supremacy of the Latin language, from which no less than a quarter of their own meagre vocabulary is derived; though driven southwards by the Romans and northwards by the Greeks, they have remained in their mountain fastnesses to this day, impervious to any of the civilizations to which they have been exposed. Christianity spread to the shores of the peninsula very early; Macedonia and Dalmatia were the parts where it was first established, and it took some time to penetrate into the interior. During the reign of Diocletian numerous martyrs suffered for the faith in the Danubian provinces, but with the accession of Constantine the Great persecution came to an end. As soon, however, as the Christians were left alone, they started persecuting each other, and during the fourth century the Arian controversy re-echoed throughout the peninsula. In the fifth century the Huns moved from the shores of the Black Sea to the plains of the Danube and the Theiss; they devastated the Balkan peninsula, in spite of the tribute which they had levied on Constantinople in return for their promise of peace. After the death of Attila, in 453, they again retreated to Asia, and during the second half of the century the Goths were once more supreme in the peninsula. Theodoric occupied Singidunum (Belgrade) in 471 and, after plundering Macedonia and Greece, settled in Novae (the modern Svishtov), on the lower Danube, in 483, where he remained till he transferred the sphere of his activities to Italy ten years later. Towards the end of the fifth century Huns of various kinds returned to the lower Danube and devastated the peninsula several times, penetrating as far as Epirus and Thessaly.