One of the greatest Roman emperors was African

Yes, north-African, i.e. Arab. Per https://en.wikipedia.org/wiki/Septimius_Severus:

> He had Italian Roman ancestry on his mother's side, and was descended from Punic forebears on his father's side [..] The Punic people, or Western Phoenicians, were a group of Semitic peoples in the Western Mediterranean who traced their origins to the Phoenicians of the coasts of Western Asia.

Augustine, one of the greatest Christian theologians, was also from North Africa.

Wasn’t the population of Carthage “replaced” several times? Xxx to Phoenician, Phoenician to Carthaginian, Carthaginian to whatever survived falling to Rome, Roman to Vandal, Vandal to Arab/Mameluke?

The same geographic location but different cultures… Before that, maybe they were part of the Sea Peoples who conquered most of the western med at the end of the Bronze Age.