The Illyrians (Ancient Greek: Ἰλλυριοί, Illyrioi; Latin: Illyrii) were a group of Indo-European-speaking peoples who inhabited the western Balkan Peninsula in ancient times. They constituted one of the three main Paleo-Balkan populations, along with the Thracians and Greeks. The territory the Illyrians inhabited came to be known as Illyria to later Greek and Roman authors, who identified a territory that corresponds to most of Albania, Montenegro, Kosovo, much of Croatia and Bosnia and Herzegovina, western and central Serbia and some parts of Slovenia between the Adriatic Sea in the west, the Drava river in the north, the Morava river in the east and the Ceraunian Mountains in the south. The first account of Illyrian peoples dates back to the 6th century BC, in the works of the ancient Greek writer Hecataeus of Miletus. The name "Illyrians", as applied by the ancient Greeks to their northern neighbors, may have referred to a broad, ill-defined group of peoples. It has been suggested that the Illyrian tribes never collectively identified as "Illyrians", and that it is unlikely that they used any collective nomenclature at all. Illyrians seems to be the name of a specific Illyrian tribe who were among the first to encounter the ancient Greeks during the Bronze Age. The Greeks later applied this term Illyrians, pars pro toto, to all people with similar language and customs.

Illyrians - Wikipedia