Here is the story:
Albanian is the only surviving dialect of Illyrian. Illyrians did not write the language. They wrote with Greek or Latin Alphabet the names of their dead. So the only way to know, is in comparing with existing names of places. let say Dalmatia which was part of Illyria, now Croatia comes from the world Delme of present day Albanian, which means Sheep, Ulcinj a city in Montenegro means wolf in Albanian , Dardania (present day Kosovo) means pear, Illyr means free man in Albanian(since Greeks and Italians had Installed slavery) Illyrians emphasized that they were free, I lire in Albanian. Also the names on burial sites are like The wind (female name) , and others that can not be translated follow Albanian language rules.
Also the genes of a 3000 year old male excavated in Croatia resembles the Albanian genes.
The only one who do not accept this fact are savage Slavs who invaded Illyria, and brought the dark age in a otherwise civilized area. As you can see the way Slavs act now, their main model is barbarism, killing and butchery. I will remind you the war in Bosnia where an animal Slav by name Ratcko Mladic gave candies to children in Bosnia, and killed in cold blooded their parents, 8000 men.So NATO started bombing them to their holes back. So they want to claim now that there was nobody when they came, in the area so they are the rightful historical owners of the land. But thanks to advancement of genetics, it shows that Slavs have Mongolian genes , like N1c, Q, C, all Asiatic genes. So, no matter what they say science is not in their side.
Hope you liked the explanation.