This is a topic which I discussed in a series of five lectures given under the auspices of the Program of African Studies at Boston University, in April 1961. It had previously been the theme of a seminar conducted during two terms in 1960–1 at the Institute of Islamic Studies, McGill University, Montreal.

When I visited Mauritania in 1960 I expected to find similarities between the culture of the West Saharan societies and that indigenous to Southern Arabia. I was not disappointed. Amidst the distinctive regional culture of the Moors there are certain traits which are difficult to explain solely by an independent evolution in a remote, yet similar, environment. Professor R. B. Serjeant, himself a specialist in Southern Arabia, was also struck by the cultural similarities after he had seen our expedition film of life in the caravan towns of Chinguetti and Wadan. There appears to be a clear case for some cultural contact, but having postulated this it is extremely difficult to tabulate or classify it. This cultural contact does not concern Mauritania alone but includes those vast areas of the Sahara and the Sudan, to east and south, which lie astride the routes leading to the Arabian peninsula.

Those who have studied the history of the Tijaniyya as a whole, are struck by the warlike character of the Umari branch which was so different from that of the other branches of the order in North West Africa and the Senegal. Hajj Umar's career as a religious warrior seems to have been shaped by two important influences: (1) the doctrines of the Tijaniyya, and (2) the ideas of Uthaman Danfodio and his son Muhammad Bello.

It has long been well known that West Africa in the nineteenth century was the scene of a number of Islamic politico-religious movements promoted by Fulani or Tukulor mujaddidīn. It is also common knowledge that these movements resulted in the establishment, inter-alia, of three great confederations of emirates each recognizing an amīr al-mu'minīn. Thus we have:

(a) The ‘Fulani Empire’ in Hausaland and neighbouring territories (founded by Usman dan Fodio from 1804) of which certain important elements persist in the governmental and social structure of the Northern Region of Nigeria down to the present day;

(b) The ‘Fulani Empire’ of Macma (founded from 1818 by Ahmadu bi Hammadi) persisting until 1863;

(c) The ‘Empire’ of Al-Hajj 'Umar b. Sa'īd (founded from 1848) which covered an area of some 150,000 square miles in the Upper Niger-Senegal region (including the land of the Caliphate of Macina which it destroyed) and was broken up by the French at the end of the nineteenth century.

The Portuguese first sailed along the coast of what is now Ghana in 1471; thereafter regular trading relations were established at numerous ports of call between Axim and the Volta. The impact made by the newcomers upon local peoples with whom they came into direct or indirect commercial contact was marked. The creation of new maritime markets stimulated trade over wide areas, and the trend away from subsistence economies gained pace (so fortuitously producing conditions necessary for the subsequent development of the slave trade). Archaeological evidence from Southern Ghana bears witness to a sharp growth in urbanization in the sixteenth century; the numerous towns that arose show a pattern of settlement quite distinct from that of the earlier Iron-Age (‘paléonégritique’) agriculturalists.

Two recent articles by Dr Mauny, inconclusive in themselves, since in the second he withdrew his earlier claim that the material of aggrey beads might be the coral-like marine growth Allopara subviolacea, inspired some independent inquiry into the question of aggrey beads. This inquiry followed three lines: (1) a re-examination of the published sources from the beginning of the sixteenth century into the nineteenth century; (2) local inquiries in Southern Ghana and, indirectly, in Western Nigeria; (3) an examination of actual beads, notably in collections in Ghana and in the British Museum. While a great deal more remains to be done, especially in following up the second and third lines of inquiry, some tentative observations may be of value, since it already appears possible to add something to the authoritative statements by Krieger and Naber on the subject.

The caravan trade, a strong chain binding Barbary, the Sahara, and the Negro territories together, was of very remote antiquity. Mauny and Lhote have convincingly shown that as early 1000 B.C. chariots were being drawn across the Sahara along two main routes: a western route from Morocco through Zemmour and Adrar to the banks of the Senegal and the Niger, and a central route from Tripoli through Cydamus (Ghadames), Ghat, and Hoggar to Gao on the Niger. By the fifth century B.C., the desert traffic—mainly in animals such as monkeys, lions, panthers, and elephants, in precious stones like carbuncles, emeralds and chalcedony, and in slaves— had become so important that ‘the Carthaginians began their great Sahara expeditions in an effort to cut out all intermediaries and to get into direct contact with the source of the riches in which they traded’. Three centuries later the Saharan trade was centred on the Tripoli-Fezzan-Bornu route (the Garamantian route) and constituted one of the main sources of the riches of Carthage. The phenomenal development of this desert traffic did not take place, however, until the introduction of the camel into Tripolitania by the Romans probably in the first century A.D. The rapid spread of the camel throughout Barbary and into the Sahara and beyond was begun by the Arabs and the Berbers. The process seemed to have gathered momentum and reached its climax during the Hilalian invasions in the middle of the eleventh century.