Sozomen's Account of the Death of Valens

Gold solidus of Valens (AD 328-378)

In AD 378 on the 9th of August, the Roman Emperor Valens was killed following the catastrophic defeat at the battle of Adrianople at the hands of the invading Goths. In this battle, a Roman field army 40,000 strong was annihilated, leaving the Eastern provinces wide open and defenseless. It is often cited as the beginning of the end of the Roman Empire as the pre-eminent power in the Mediterranean world.

A detailed description of the battle and its aftermath may be found in the Roman Antiquities of Ammianus Marcellinus. Another account, written by Sozomen about 50 years after the event, contains some additional details surrounding the battle and the death of Valens that are not recorded in Marcellinus's account: 

Those in every city who maintained the Nicene doctrine now began to take courage, and more particularly the inhabitants of Alexandria in Egypt....The Emperor Valens [a follower of the Arian heresy] very naturally was so distracted by other affairs, that he had no leisure to attend to these transactions. He had no sooner arrived at Constantinople than he incurred the suspicion and hatred of the people. The barbarians were pillaging Thrace, and were even advancing to the very suburbs, and attempted to make an assault on the very walls, with no one to hinder them.

The city was indignant at this inertness; and the people even charged the emperor with being a party to their attack, because he did not sally forth, but delayed offering battle. At length, when he was present at the sports of the Hippodrome, the people openly and loudly accused him of neglecting the affairs of the state, and demanded arms that they might fight in their own defense. Valens, offended at these reproaches, immediately undertook an expedition against the barbarians; but he threatened to punish the insolence of the people on his return, and also to take vengeance on them for having formerly supported the tyrant Procopius.

When Valens was on the point of departing from Constantinople, Isaac, a monk of great virtue, who feared no danger in the cause of God, presented himself before him, and addressed him in the following words: "Give back, O emperor, to the orthodox, and to those who maintain the Nicene doctrines, the churches of which you have deprived them, and the victory will be yours."

The emperor was offended at this act of boldness, and commanded that Isaac should be arrested and kept in chains until his return, when he meant to bring him to justice for his temerity.

Isaac, however, replied, "You will not return unless you restore the churches."

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And so in fact it came to pass. For when Valens marched out with his army, the Goths retreated while pursued. In his advances he passed by Thrace, and came to Adrianople. When at not great distance from the barbarians, he found them encamped in a secure position; and yet he had the rashness to attack them before he had arranged his own legions in proper order. His cavalry was dispersed, his infantry compelled to retreat; and, pursued by the enemy, he dismounted from his horse, and with a few attendants entered into a small house or tower, where he secreted himself.

The barbarians were in full pursuit, and went beyond the tower, not suspecting that he had selected it for his place of concealment. As the last detachment of the barbarians was passing by the tower, the attendants of the emperor let fly a volley of arrows from their covert, which immediately led to the exclamation that Valens was concealed within the building. Those who were a little in advance heard this exclamation, and made known the news with a shout to those companions who were in advance of them; and thus the news was conveyed till it reached the detachments which were foremost in the pursuit. They returned, and encompassed the tower. They collected vast quantities of wood from the country around, which they piled up against the tower, and finally set fire to the mass. A wind which had happened to arise favored the progress of the conflagration; and in a short period the tower, with all that it contained, including the emperor and his attendants, was utterly destroyed. 

Valens was fifty years of age. He had reigned thirteen years conjointly with his brother, and three by himself. [Taken from The Ecclesiastical History of Sozomen, Book VI, Chapters 39 & 40]