The movement of the Slavs from their original homeland north of the Carpathians to other parts of East Central Europe is apparently linked in large part to the invasion between the fifth and sixth centuries of nomadic peoples from the east.

The Huns, Alans, and Kutrigur Bulgars in turn subject certain Slavic tribes and often take them along on raids against the Eastern Roman Empire.

The Kutrigur Bulgars probably originated as a Turkic tribe of Central Asia and arrived in the European steppe west of the Volga River with the Huns about 370; retreating with the Huns, they resettled about 460 in an arc of country north and east of the Sea of Azov.

Hired by the East Romans in 480 to fight against the Ostrogoths, the Bulgars subsequently have attracted by the wealth of the empire.

From 493, the Bulgars continually attack the western Danubian provinces of the Empire.

Meanwhile, small Slavic groups have in the fifth century begun settling outlying regions in the region of what is today Bulgaria.

The Slavs, characteristically sedentary farming and livestock-raising tribes, speak an Indo-European language and organize themselves into clans ruled by a council of family chiefs, holding in common all land and significant wealth.