The Illyrians (, ; ) were a conglomeration of Indo-European peoples and tribes in the Balkan Peninsula, Southeastern Europe.
There are different views and still no agreement among scholars about the Paeonians/Paeones ethnic and linguistic kinship. Some such as Wilhelm Tomaschek and Paul Kretschmer claim that the language spoken by the Paeonians belonged to the Illyrian family, while Dimitar Dechev claims affinities with Thracian. Irwin L. Merker considers that the language spoken by the Paeonians was closely related to Greek (if it was a distinct language and not a dialect of ancient Greek), a Hellenic language with "a great deal of Illyrian and Thracian influence as a result of this proximity".