A significant number of sub-Saharan Africans live in desert and coastal communities, mixed with Arabs and Berbers. Most of them are descended from former slaves--the last slave caravan is said to have reached Fezzan in 1929--but some immigrated to Tripoli during World War II. In recent years, waves of migrant workers from Mali, Niger, Sudan, and other Sahelian countries have arrived. A majority work as farmers or sharecroppers in Fezzan, but some have migrated to urban centers, where they are occupied in a variety of jobs considered menial.
Another distinct but numerically small group of blacks, the harathin (plowers, cultivators) have been in the Saharan oases for millennia. Their origins are obscure, but they appear to have been subservient to the Tuareg or other Libyan overlords for at least the last millennium. As with other blacks, their status has traditionally been quite low. In Libya as a whole, dark-skinned people are looked down upon, the degree of discrimination increasing with the darkness of the skin.