Visigoths
The Visigoths were a confederacy of Germanic tribes, who migrated from the Baltic area to the Danube River, pressed by the advancing Huns. They were offered entrance into Rome territory on peaceful terms by the Emperor Valens. However, the Romans did not provide the Visigoths with enough food, forcing them to sell their children into slavery in exchange for the meat of dogs.
So the Visigoths rose up against the Romans and crushed their main army at the Battle of Adrianople. As the Roman Empire became more shaky, they found it more difficult to stop the Visigoths and other barbarian tribes. This culminated in the Visigothic sacking of Rome in 410 A.D., under the rule of Alaric I. Saint Augustine chronicled this horrific defeat, and the shockwave it sent throughout the world, intellectually and physically, in his major work, City of God."
Following the collapse of the Roman Empire, the Visigoths gained control over Rome when they deposed Romulus Augustulus, the last emperor, in 476 A.D. However, they were later defeated by the Ostrogoths under the command of Theoderic, on orders from the Byzantine ruler Zeno.
The Visigoths eventually moved to settle South Western Gaul (France) with Tolouse as their capital, but were defeated by the Franks under Clovis and henceforward had their territory in Spain with Toledo as their capital.
The Visigothic Kingdom in Spain fell to the Isalmic Moors in AD 711. Their last king was Roderick.