There is an opinion by many experts in the Slavic studies that ancient Sarmatians, Scythians, and Antes were the Slavs and, therefore, proto-Croats and proto-Serbs maybe parts of them. In addition, most probably that ancient Balkan Illyrians of the Indo-European origin, dominating the Central and West Balkans, have been, in fact, autochtonous Slavs of South-East Europe.