The population of ancient Carantania had a polyethnic structure. The core stratum was represented by two groups of Slavs who had settled in the Eastern Alps region in late 6th century. Other ethnic elements included Croats, Dulebes and the descendants of the Romanised aboriginal peoples (Noricans), the latter which is attestable on the basis of a number of place names. It is also possible that traces of Avars, Bulgars and the Germanic peoples were present among Carantanians.