This is an ancient district of Africa in Roman times. In a vague sense it meant only the land of the Moor's and lay W of Numidia, but more specifically it usually included most of present-day N Morocco and W Algeria. The district was not the same as modern Mauritania. It was a complex of native tribal units, but by the 2d cent. BC when Jugurtha of Numidia was rebelling against Rome, Jugurtha's father-in-law, Bocchus, had most of Mauretania under his control. The Roman influence became paramount, and Augustus, having met opposition in restoring Juba II (see under Juba I ) to the throne of Numidia, placed him instead (25 BC) as ruler of Mauretania. Revolts later occurred, and Mauretania was subdued (AD 41-AD 42); Emperor Claudius I made it into two provinces Mauretania Caesariensis, with Caesarea (modern Cherchel) as capital, and Mauretania Tingitana, with Tingis (modern Tangier) as capital. Roman influence was never complete, and native chieftains remained powerful.

With the onset of the barbarian invasions, Roman control weakened, and by the end of the 5th cent. AD it had disappeared.