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Illyrians has come to refer to a broad, ill-defined "Indo-European" group of peoples who inhabited the western Balkans (Illyria, roughly from the Albanian and Montenegro border to southern Pannonia) and even perhaps parts of Southern Italy in clical times into the Common era, and spoke Illyrian languages. It is, however, less believable that in reality there was such a broad group that self-identified as Illyrians, and some argue that the ethnonym Illyrioi came to be applied to this large group of peoples by the ancient Greeks, Illyrioi having perhaps originally designated only a single people that came to be widely known to the Greeks due to proximity. Indeed, such a people known as the Illyrioi are supposed to have occupied a small and well-defined part of the south Adriatic coast, around Skadar Lake astride the modern frontier between Albania and Montenegro. The name may then have expanded and come to be applied to ethnically different peoples such as the Liburni, Delmatae.