The details of the period 354 to 378 are so well known because they are covered by one of the finest of the Roman historians, Ammianus Marcellinus (330-c.395). Ammianus was Greek by birth, a native of Antioch, but he provides a good example of how the empire had imbued Greeks with loyalty to a Roman ideal. Having served with the Roman army he spent the last years of his life in Rome and wrote in Latin. He was nostalgic for the earlier days of Rome, contrasting the frugal habits of the early republic with the decadence of the grandees he observed around him in the city. His descriptions of their wealth and alleged corruption and their passage through the streets surrounded by a mass of slaves are among the most evocative portraits in his work.
Ammianus’ history began in ad 96, the date at which Tacitus’ history had ended. However, all the early books are lost. Those that survive (from 354) are based on personal experience and contemporary evidence and provide by far the best non-Christian perspective on an empire that was preoccupied with political survival. Ammianus’ work is remarkable at many levels, quite beyond the wealth of detail it provides. He can create, as Tacitus could, the atmosphere of terror emanating from a man who had absolute power, and, in the closing chapters of his work, he explains the feelings of impotence engendered by the hordes of ‘barbarians’ who swept into the empire before the cataclysmic defeat of the Roman armies at Adri-anople in 378 (see below).
Ammianus’ world, therefore, is one where pressures crowd on those in power and their reactions are often vicious in return. He notes how corruption spreads from the top down during the reign of Constantius, for whom he had a particular aversion. In Pannonia one of the prefects, Probus, attempted to ingratiate himself with the emperor by gathering taxes with such force that the poor were sometimes reduced to suicide while the rich moved to escape his depredations. This is the picture which has survived of the fourth century in general, one in which Roman rule became increasingly tyrannical. Whether it is the full truth is difficult to say. As has been suggested in earlier chapters, Roman rule had always been weighted towards the elites at the expense of the poor with little mercy shown for those who offended the state, but the reports of brutality of superiors in the bureaucracy against their inferiors that Ammianus relates are certainly new.