A region in the northwestern part of the Balkan Peninsula, where in 27 BC, Augustus (known as Gaius Julius Caesar Octavianus) established the province of Illyricum. Later on Illyricum was divided into two parts: Lower (Dalmatia) and Upper (Pannonia). At the time of the emperor Constantine I the Great Illyricum comprised of Upper Moesia, Raetia, Noricum, Dacia, Macedon and Greece.
After the beginning of the 5th century the province was subjected to devastating invasions of Germanic tribes, called Ostrogoths and Visigoths.
In the 6th century Slavic tribes began to gradually settle in the province.
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