Attila was the fierce 5th century leader of the barbarian group known as the Huns who struck fear in the hearts of the Romans as they plundered everything in their path, invaded the Eastern Empire and then crossed the Rhine into Gaul.
When Attila and his brother Bleda inherited the empire of the Huns from their uncle Rugilas, it extended from the Alps and Baltic to the Caspian Sea.
In 441, Attila captured Singidunum (Belgrade). In 443, he destroyed towns on the Danube, then Naissus (Niš) and Serdica (Sofia), and took Philippopolis. He then destroyed imperial forces in Gallipoli. He later went through the Balkan provinces and into Greece, as far as Thermopylae.
Attila's advance in the west was checked at the 451 Battle of the Catalaunian Plains (Campi Catalauni), thought to be in Chalons or Troyes, in eastern France. The forces of Romans and Visigoths under Aetius and Theodoric I defeated the Huns under Attila for the only time.