Although these languages are all members of the Indo-European language family, the relationships between them are unknown. Classification of the languages spoken in the region is severely hampered by the fact that, except for Ancient Greek, they are all scantily attested. Furthermore, many of the individuals who have published studies on these languages have had strong patriotic or nationalistic interests, which compromises the scholarly value of their work.
It is generally considered plausible that Albanian evolved from one of the non-Greek languages of the region, but attempts to connect it to a specific language have been fruitless (see Origin of the Albanians).