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. 3 _The Arrival of the Slavs in the Balkan Peninsula_, A.D. 500–650 The Balkan peninsula, which had been raised to a high level of security and prosperity during the Roman dominion, gradually relapsed into barbarism as a result of these endless invasions; the walled towns, such as Salonika and Constantinople, were the only safe places, and the country became waste and desolate. The process continued unabated throughout the three following centuries, and one is driven to one of two conclusions, either that these lands must have possessed very extraordinary powers of recuperation to make it worth while for invaders to pillage them so frequently, or, what is more probable, there can have been after some time little left to plunder, and consequently the Byzantine historians’ accounts of enormous drives of prisoners and booty are much exaggerated. It is impossible to count the number of times the tide of invasion and devastation swept southwards over the unfortunate peninsula. The emperors and their generals did what they could by means of defensive works on the frontiers, of punitive expeditions, and of trying to set the various hordes of barbarians at loggerheads with each other, but, as they had at the same time to defend an empire which stretched from Armenia to Spain, it is not surprising that they were not more successful. The growing riches of Constantinople and Salonika had an irresistible attraction for the wild men from the east and north, and unfortunately the Greek citizens were more inclined to spend their energy in theological disputes and