Numidia, the name in ancient times for a region of North Africa. The heart of Numidia lay in what is now eastern Algeria. The Numidians, a Berber people, were originally nomadic horsemen who first aided, and later opposed, Carthage in the Punic Wars. Roman troops defeated the Numidians in the Jugurthine War (111–105 B.C.). After Numidia was conquered by the Romans in 46 B.C., the region prospered. Cirta (now Constantine) and Hippo, the see of Saint Augustine, were the main cities. Numidia fell successively under Vandal and Byzantine rule before the Arabs conquered it in the seventh century A.D.