The desert trade in enslaved people, already centuries old by 1450, continued and in places intensified through the early modern period. Captives were taken in raiding and warfare in the Sahel and the savanna belt, marched to desert-edge markets such as Timbuktu, Agades, Kano and Kobbei, and carried north by caravan to Morocco, the Ottoman Regencies of Algiers, Tunis and Tripoli, and Egypt, where they were absorbed into domestic service, agriculture, the military and the harem. The Moroccan conquest of Songhay in 1591 and the later creation by Mawlay Isma'il of a standing army of enslaved black soldiers, the Abid al-Bukhari, are the clearest instances of state organisation of the traffic. Women and children formed a much larger share of this trade than of the Atlantic trade, and mortality on the desert crossing was high. The volume is genuinely unknown: the figures in circulation derive from Austen's reconstructions and later syntheses and should be read as orders of magnitude rather than counts.
Saharan and North African merchants, and the Moroccan and Ottoman states that taxed and used them, moved enslaved people north across the desert from the Sahel and the Sudan to Morocco, Algiers, Tunis, Tripoli and Egypt
Ralph Austen's censuses of the Saharan trade, built from North African market records, caravan accounts and demand estimates, give roughly 4,000-7,000 captives a year in this period, or on the order of 1.5 million between 1450 and 1750, with wide error margins. The populations raided - Kanem-Bornu's tributaries, the Hausa lands, the Niger bend, Darfur and Kordofan - were never enumerated, changed constantly with the rise and fall of states, and cannot be aggregated into a single base.
No total exists. Contemporary travellers describe heavy mortality on the desert crossings and the routes are marked by burial sites, and historians generally assume losses at least as high as those of the Atlantic middle passage, but there is no series of records from which a figure could be derived.
The predominance of women and children among those carried north, their use as domestic and sexual slaves, and the castration of some boys for the eunuch trade are described in Arabic chronicles, market records and European travellers' accounts and are summarised in the historiography reviewed by Austen and Rönnbäck.
Mali, Niger, Libya, Morocco, Sudan, Egypt