The Scordisci were an Iron Age cultural group who emerged after the Celtic settlement of Southeast Europe, and who were centered in the territory of present-day Serbia, at the confluence of the Savus (Sava), Dravus (Drava), Margus (Morava) and Danube rivers. They were historically notable from the beginning of the third century BC until the turn of the common era, and consolidated into a tribal state. At their zenith, their core territory stretched over regions comprising parts of present-day Serbia, Croatia, Bulgaria and Romania, while their influence spread even further. After the Roman conquest in the 1st century AD, their territories were included into the Roman provinces of Pannonia, Moesia and Dacia.

Gallic groups, originating from the various La Tène chiefdoms, began a southeastern movement into the Balkans from the 4th century BC. Although Gallic settlements were concentrated in the western half of the Carpathian basin, there were notable incursions and settlements within the Balkans.