The Ostrogoths were a branch of the later Goths (the other major branch being the Visigoths). 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. Migrating 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.