9 August 378 CE

The fall of the Roman Empire in the late classical age was a slow but irresistible process. Few battles signalled its eventual fate more completely than the battle outside the town of Adrianople (modern-day Edirne in western Turkey), where an army of Gothic tribes all but annihilated a large Roman army led by the emperor himself, Flavius Valens Augustus. The defeat had not been a foregone conclusion, as the Goths had been nervous of a pitched battle with seasoned Roman troops. The tide was turned by the late arrival of reinforcements for the Goths. From a position of numerical inferiority, they suddenly found themselves on equal terms with the enemy. Valens’s prevarication and incompetence then turned what might have been a military stalemate into a comprehensive rout.

A painting by the French artist Évariste Vital Luminais (1821-96) shows an army of Goths approaching Rome. The Goths symbolized the barbarian threat to the Roman Empire and the Roman defeat at Adrianople in 378 indicated clearly just how dangerous that threat was. In 410 Rome itself was sacked.

Leading up to the battle, the Roman Empire had been trying to find ways to live in peace with the settlers and warriors who were moving in large numbers from mainland Asia into the heart of Europe. In the mid-fourth century, beyond the frontier of the empire in the Balkans, the Huns emerged as a powerful and predatory new kingdom in central Asia, causing major movements of population. The Huns pushed back the Alans, whose pressure in turn pushed the Gothic Greuthungi and Tervingi kingdoms further west and southwest. In 376, large numbers, perhaps hundreds of thousands, of refugee Tervingi arrived on the Danube frontier with Rome and petitioned for permission to cross into Roman territory to escape the apparently unstoppable Huns. Negotiations took time as the emperor was in Antioch, on the southern coast of modern Turkey, not in Constantinople. Valens decided to agree to a treaty that would allow the Goths to cross the river, in the hope that he could use their manpower for his wars in the east against Persia. The Goths crossed over the river and were immediately subjected to harsh treatment by the local Roman generals, who stole the food allocated to the refugees and traded dog meat instead, at the rate of one dog in exchange for a Gothic child to be sold into slavery.

While the Tervingi were being dispersed south, the leaders of the Greuthungi Goths, Alatheus and Saphrax, who had been refused entry to the empire, slipped across the Danube unnoticed and set up a large camp unsupervised by the Romans. Meanwhile, the local Roman commander Lupicinus invited the leaders of the Tervingi, Fritigern and Alavivus, to a feast in his headquarters in Marcianople; it is not clear if he intended to kill them, but he killed their bodyguard. The Goths outside the city threatened to break in and Lupicinus thought better of his plot. Fritigern escaped but Alavivus was not seen again. As a result, the Goths rebelled against Roman abuse and laid waste to much of Thrace. The Roman armies in the west, led by Valens’s young nephew Gratian, sent reinforcements, but the main army would not arrive until the late summer. Valens decided to snuff out the Gothic threat. He appointed Sebastianus as commanding general of his cosmopolitan army, drawn from all over the Eastern Empire, and on 11 June 378 set out from Constantinople to destroy the army of Fritigern. He set up camp in Adrianople and on the morning of 9 August, after rejecting overtures for an armistice from the Goths and receiving intelligence that the enemy numbered only 10,000, took his army out to the plain where the Goths had drawn up their forces. Valens was confident that a Roman victory was assured.

The record of the battle has not survived in great detail in the one classical account that we have. Gratian was approaching but would not arrive for some days or weeks. Valens thought his help was not needed, but he was outmanoeuvred by Fritigern. While the Roman army stood in the baking sun in its usual battle order, the Goths lit grass fires whose smoke, like a twentieth-century gas attack, was designed to leave the enemy troops temporarily incapacitated. At the same time, Fritigern sent further envoys to Valens, ostensibly to seek peace but in fact to stall for time while he waited for his adopted allies, the Greuthungi of Alatheus and Saphrax, to arrive. In the confusion, the right wing of the Roman army began engaging with the Goths in front of them. What followed was, by Roman standards, a chaotic battle. The Roman line was distorted and then, at the critical moment, perhaps 10,000 new warriors appeared – the army of the Greuthungi – to cave in the Roman left flank. The newcomers turned the tide as they overwhelmed the now numerically inferior attackers. The Roman cavalry on the left found they had ridden too far and were cut off and slaughtered. As a result, the unprotected infantry line bent back on itself, leaving the soldiers with insufficient room to fight. The Goths swarmed over the Roman line, killing thousands where they stood. Roman reserves melted away from the battlefield in fear. Two-thirds of the cream of Rome’s eastern army were slaughtered, along with the emperor Valens, whose body was never recovered. It was later variously recorded that Valens had been shot by an arrow, or that he had been burnt to death in a nearby farmhouse. His senior commanders, Traianus and Sebastianus, also perished in the massacre.

For the Roman Empire, Adrianople was a disastrous and humiliating rout. It signalled around the known world that the Roman frontier could no longer act as an effective barrier, and hundreds of thousands of migrants pushed into the empire over the following decades. But it was a battle that, with better judgement, intelligence and operational understanding, the Romans might have won. Fritigern was fortunate that Alatheus and Saphrax arrived when they did. We do not know why they came to his aid, but their arrival helped write a new chapter in the history of the fall of Rome. Only forty years later, the Goths sacked the very capital of the empire.