the concept that the strata have innate pollution and therefore they are stigmatized, however there is no evidence that their Islamic belief integrated the differences between the socially differentiated castes in their society to have been divinely sanctioned. The Mandara people also featured an endogamous slave strata. Toubou people The Toubou people are an Islamic ethnic group inhabiting northern Chad, southern Libya, northeastern Niger, and northwestern Sudan. The Toubou people, states Jean Chapelle – a professor of History specializing on Chadian ethnic groups, have been socially stratified with an embedded caste system.Jean Cabot (1965), Trois ouvrages sur les populations du Nord du Tchad de Jean Chapelle, Annie Lebeuf et Albert Le Rouvreur, Annales de Géographie, Volume 74, Numéro 401, pages 104-107, Quote: "des castes particulières: Azza (forgerons, chasseurs, tanneurs), les Kamadjas (...)" The three strata have consisted of the freemen with a right to own property, the artisanal castes and the slaves. The endogamous caste of Azza (or Aza) among Toubou have the artisanal occupations, such as metal work, leather work, pottery and tailoring, and they have traditionally been despised and segregated by other strata of the Toubou, much like the Hadahid caste in southeastern Chad among the Zaghawa people. Marriage between a member of the blacksmith caste and a member from a different strata of the Toubou people has been culturally unacceptable. The strata locally called Kamadja were the slaves. The language used by the Azza people is a variant of the Tebu language, but mutually intelligible. Zaghawa people The Zaghawa people, also called Beri or Zakhawa, are a Central African Muslim ethnic group of eastern Chad and western Sudan, including Darfur. The Zaghawa are mentioned in classical Arabic language texts by Islamic historians and geographers. The century in which the Zaghawa people adopted Islam has been a subject of debate and little consensus, with estimates ranging from the 13th to the early 17th century. The Zaghawa society has been socially stratified and has included castes. The upper strata has been of nobles and warriors, below them have been the traders and merchants, below whom have been the artisan castes called the Hadaheed (or Hadahid).F. D. Klingender (1942), Gericault as Seen in 1848, The Burlington Magazine, Vol. 81, No. 475 (Oct., 1942), pages 254-256 These castes have been endogamous, and their inherited occupations have included iron work, hunters, pottery, leatherwork and musicians such as drummers. The artisan work has