The Roman who stopped Attila learned war as a boy hostage among the Huns
As a youth Flavius Aetius was handed over as a hostage, first to the Visigoth king Alaric and then to the court of the Huns. Those years gave him allies he later used to seize power in Rome, and in 451 he turned an army of Romans and Goths against Attila himself.
Aetius was born around 390 at Durostorum, today Silistra in Bulgaria, the son of a Roman general from Scythia and an aristocratic Italian mother. Between 405 and 408 he lived as a hostage with Alaric, and then with the Hun king Uldin and his successor. Some modern historians think that upbringing among warrior peoples gave him a toughness rare among Roman commanders of his day.
His Hun friendships were a political weapon. In 425 he backed the usurper Joannes and arrived in Italy with a large Hun army just after Joannes was killed; he bargained with the regent Galla Placidia, sending the Huns home in return for command in Gaul. When his rival Bonifacius was promoted over him in 432, Aetius fought him at Rimini, lost the battle but saw Bonifacius die of his wounds, fled to the Hun king Rugila and returned with support. He then married Bonifacius's widow. For roughly two decades from 433 he was the most powerful man in the West.
Much of that time went on holding Gaul together by force and bargaining. He repeatedly drove back Visigoths and Franks, settled Burgundians near Lake Geneva and Alans along the Loire, and suppressed rural Bagaudae uprisings. A massacre of Burgundians by his Hun federates in 437 probably inspired the German epic the Nibelungenlied.
When Attila invaded Gaul, Aetius and the senator Avitus persuaded the Visigoth king Theodoric I, Franks, Burgundians and others to join Rome, relieving besieged Orléans. On 20 June 451 they met Attila at the Catalaunian Plains; Theodoric died but the invasion ended. Edward Gibbon hailed Aetius as the terror of barbarians, and he is often called the Last of the Romans. Emperor Valentinian III murdered him in 454.
Source: Flavius Aetius