How did Roman rule affect the territory of modern Bosnia and Herzegovina?

During the 2nd and 1st centuries BCE, the Romans extended their conquests into the territory of modern Bosnia and Herzegovina, where they encountered primarily Illyrian tribes. Most of this region was subsequently incorporated into the Roman province of Dalmatia.1

Roman rule significantly influenced the area through a long process of cultural assimilation. Among the physical remnants of this period is a former Roman rest center located at Ilidža, near modern Sarajevo, which remains known for its sulfurous spa.23

By the 4th and 5th centuries CE, however, Roman control in the region weakened as Roman armies faced heavy defeats from invading Goths. Following the eventual expulsion of the Goths by the Byzantine emperor Justinian I in the 6th century, the territory transitioned into the Byzantine sphere of influence, setting the stage for the subsequent settlement of Slavic peoples.1