The Ostrogoths, under Theodoric the Great, established a kingdom in Italy in the late 5th and 6th centuries. The Ostrogoths traced their origins to the Greutungi and a semi-legendary kingdom north of the Black Sea in the 3rd and 4th centuries. They were part of the Invasion of Rome. Invading southward from the Baltic Sea, the Ostrogoths, at the time known as the Greuthungi, built up a huge empire stretching from the Dniester to the Volga River and from the Black Sea to the Baltic shores. The Ostrogoths were probably literate in the 3rd century, and their trade with the Romans was highly developed. Their Danubian kingdom reached its zenith under King Ermanaric, who is said to have committed suicide at an old age when the Huns attacked his people and subjugated them in about 370.
After their subjugation by the Huns, little is heard of the Ostrogoths for about 80 years, after which they reappear in Pannonia on the middle Danube River as federates of the Romans. However, a pocket remained behind in the Crimea when the bulk of them moved to central Europe, and these Crimean Ostrogoths existed until at least the 16th century. After the collapse of the Hun empire after the Battle of Nedao (453), the Ostrogoths under Theoderic the Great first moved to Moesia (c. 475–488) and later conquered the Italian Kingdom of the German warrior Odoacer. Theodoric became king of the Ostrogothic Kingdom in 493 and died in 526.
A period of instability then ensued, tempting the Eastern Roman Emperor Justinian to declare war on the Ostrogoths in 535 in an effort to restore the former western provinces of the Roman Empire. Initially, the Byzantines were successful, but under the leadership of Totila, the Goths reconquered most of the lost territory until Totila's death at the Battle of Taginae. The war lasted for almost 20 years and caused enormous damage and depopulation of Italy. The remaining Ostrogoths were absorbed into the Lombards who established a kingdom in Italy in 567.