Battle of Adrianople

On 9 August 378 CE, the eastern Roman Emperor Valens led his army against a Visigothic force that had crossed the Danube under desperate conditions, fleeing the Hunnic advance from the east. Valens, hoping for a quick victory before his co-emperor Gratian could arrive and share the glory, attacked without waiting for western reinforcements. The Roman cavalry routed early in the battle, leaving the infantry encircled and annihilated; Valens himself was killed, becoming the first Roman emperor to die in battle against a foreign enemy in over a century. The catastrophe opened the Balkans to Gothic settlement on Roman soil under their own leadership, establishing the precedent of autonomous barbarian kingdoms within imperial territory. Adrianople is often cited as the opening act of the process that would end the Western Empire a century later.

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