378
The Battle of Adrianople
One of the most consequential battles in human history took place on this date in 378 on a field outside what was then the Roman city of Adrianople and is now Edirne, Turkey. The forces of the Emperor Valens were overcome by Gothic tribesman, triggering the collapse of the Roman empire and the end of civilization in the West.
For centuries Rome had held a border stretching from the North Sea to the Black Sea, a line of fortifications that held back hordes of barbarian tribes. Many times this line was pierced, allowing these Germanic invaders to rampage for a time before being driven back. The Roman empire took to allowing some of these tribes to settle in underpopulated border areas to keep their more hostile cousins out; the Roman army also recruited heavily from warlike peoples outside the boundary.
In the 370s the Huns arrived in Europe after decades of migration westward. These fearsome folk disrupted the Germanic kingdoms in eastern Europe and caused some of the Gothic tribes to beg Rome to be allowed inside the empire. This was permitted but almost immediately the Goths began to complain of ill-treatment by Roman officials and conflict erupted inside the borders. In 378 the eastern emperor Valens marched out against the barbarians north of the capital Constantinople. He found that their army had fortified their wives, children and possessions inside a wagon circle and had deployed their fighting men around it. In the battle that followed the Romans were outflanked and comprehensively defeated with the Valens himself being killed.
Roman armies had been wiped out before; Roman emperors had died in battle before. What made Adrianople different was that these victorious barbarians were never expelled. The Goths stayed inside the empire and wandered for two generations inside its borders, sometimes being bought off, sometimes pillaging where they travelled. In 410 they sacked Rome causing a shiver of horror in the civilized world before they wandered off again to invade Gaul and finally settle in Spain. Their example encouraged the onslaught of more tribes — Alans, Ostrogoths, Alamanni, Vandals, Burgundians, Angles, Saxons, Picts, Jutes, Suevi and Huns — and by 476 the Roman Empire in the West had ceased to exist.
Both Valens and the Goths who killed him were Christian, and both were of the Arian (non-Trinitarian) variety. Valens would be the last of the Arian emperors; Theodosius who succeeded him would make Trinitarian Christianity the official religion of the empire. This means that the barbarians who overran the West would be either heretics or pagans and would rule over peoples of what one could call a Catholic belief. The Church in the West faced enormous challenges in surviving and eventually converting the conquerors. The methods, political compromises, and language that the popes use to accomplish this would create a distinct form of Christianity and encourage the split that developed between the Eastern and Western Churches. Had Valens triumphed at Adrianople the world might have looked very different than it came to.