Then arose upon the Punic ruins a great metropolis which took rank as the third city in the Roman Empire, rivaling in her opulence and glory Antioch, Alexandria, even Rome herself. The new Carthage was richer, more beautiful, more luxurious than the old, the repository of the arts of Greece and the sciences of Rome, and the cradle of early Christianity. Whereas the Phenicians had sought merely to produce an effect of massive weight, the architecture of the Roman city was characterized by beauty of outline and an almost unequaled wealth of sculptural detail and richness of decoration. During the second century A.D., Carthage, its material prosperity now greater than ever, was the scene of the persecution and martyrdom of thousands of Christians, even women of the noblest birth, such as Perpetua and Felicitas, being devoured in its amphitheater by the lions. Notwithstanding the immense importance of Carthage, the Romans, curiously enough, made but little attempt to expand their African frontiers, their trans-Mediterranean territory at this period consisting of little more than that portion of the modern Tunisia which lies to the east of a line drawn from Tabarca to Sfax. This formed the Provincia Africa, and it was from this little triangle of land that the whole of the vast continent took its name. But the haughty spirit and iron will of the Romans were broken by Alaric the Goth, who sacked Rome in 410, so that the empire was already tottering to its fall when the terrible Genseric, deformed in body and in mind, crossed the Straits of Gibraltar with his barbarian hordes, swept like a cyclone along the northern shore of Africa, took Carthage in 439, and made it a Vandal stronghold. But the African empire which the Vandals had built in a day perished in a night; for less than a century later, in 533 to be exact, the barbarians were defeated and Carthage occupied by a Byzantine army under the leadership of the famous soldier Belisarius—or Beli-tzar, the White Prince, to give him his proper name. Within three months of his landing Belisarius was able to send word to his master Justinian, at Constantinople, that the Provincia Africa was once more a part of the empire of Rome.