Roman domination of the northern Mediterranean coasts of Africa began when Carthago was defeated. The Roman empire in the following century controlled all the coasts from the Nile valley to the Atlantic Ocean of actual Morocco
The Roman military presence of North Africa was relatively small if related to other areas of the empire, consisting of about 28,000 troops and auxiliaries in Numidia and the two Mauretanian provinces. Starting in the 2nd century CE, these garrisons were manned mostly by local inhabitants, because the area was considered fully pacified and nearly totally romanised.
Aside from Carthage, urbanization in North Africa came in part with the establishment of settlements of veterans under the Roman emperors Claudius, Nerva, and Trajan. (Wikipedia)