The dates and circumstances of early references to Jenne have led historians to conclude that the city originated relatively late in time. It is widely believed that the city developed simultaneously with Timbuktu in the mid-thirteenth century as an artifact of trans-Saharan trade. Persistent oral traditions of the foundation of Jenne in the eighth century are generally discounted.

Recent archaeological excavations at the ancestral site of Jenne-jeno have established that iron-using and manufacturing peoples were occupying the site in the third century B.C. The settlement proceeded to grow rapidly during the first millennium a.d., reaching its apogee between a.d. 750 and 1100, at which time the settlement exceeded 33 hectares (82 acres) in size. The archaeological data are supported by the results of site survey within a 1,100-square-kilometre region of Jenne's traditional hinterland. During the late first millennium a.d., several nearby settlements comparable in size to Jenne-jeno existed, and the density of rural settlements may have been as great as ten times the density of villages in the hinterland today.

Evidence from excavation and survey indicates that Jenne participated in inter-regional exchange relations far earlier than previously admitted. The stone and iron in the initial levels at Jenne-jeno were imported from outside the Inland Delta; levels dated to c.a.d. 400 yield copper, presumably from distant Saharan sources. The importance of the abundant staple products of Jenne's rural hinterland, including rice, fish and fish oil, is examined in a reassessment of the extent of inter-regional commerce and the emergence of urbanism during the first millennium a.d. Jenne-jeno may have been a principal participant in the founding of commercial centres on the Saharan contact zone of the Bend of the Niger, rather than a product of the luxury trade serviced by those centres.

The role of the ‘Lower Zambezi complex’ which developed out of Portuguese and African interaction is examined in the light of recent research in the Gwembe valley, an area of the Middle Zambezi on the far periphery of Portuguese penetration from the east coast. The origins of Lower Zambezi contacts with the peoples of southern Zambia are traced to the late seventeenth century and their development and expansion are examined, on the basis of oral tradition and written sources, through the reopening of Zumbo in 1862, the defeat of the Ndebele at the Kafue confluence around 1870 and the consequent establishment of permanent trading posts in the Gwembe, down to the late 1880s when the increasingly disruptive activities of the Chikunda and their muzungu leaders led to general and successful resistance against them in the form of an armed rising. The effects of the ‘Lower Zambezi complex’ are related to the development of political authority and the introduction of technical and cultural innovations in the Gwembe. Chikunda and muzungu activities are shown to have differed in their effects between the Gwembe and their much better-known and more destructive penetration of the Luangwa valley in the 1880s, partly because of the decentralized nature of Gwembe society.

Salt has been produced in Ghana since at least the sixteenth century at many coastal sites. By the nineteenth century commercial production was concentrated in the lagoons east of Accra, and especially at Songor Lagoon just west of Ada. Here the Ada Manche and the priesthood controlled production. Much salt consumed in Asante and further north came from Accra, Ningo and Songor, and an increasing proportion went up the Volta River by canoe. The share of salt trade in the hands of the Ada traders is reflected in their virtual monopoly of the river traffic and their settlement in trading communities along the river. The British attempted to regulate and tax the trade, but market forces were more important in determining price. Salt from Ada was generally preferred to imported salt and to salt from other local sources, but the alternative of imported salt helped regulate the local prices. The importance of Daboya as a source of salt seems to have been somewhat exaggerated. Salt from Ada continued to predominate in much of Ghana in the twentieth century, but the river traffic was gradually replaced by motor transport, and the hold of the Adas on the distributive network broken. Salt continued to be produced by traditional methods at Songor until quite recently. It is still produced by traditional means for a fairly wide sale at Keta Lagoon, east of the Volta.

La trypanosomiase ou maladie du sommeil existe a l'état endémique en Afrique tropicale et done en Côte d'Ivoire où elle a constitué de 1900 à 1945 un grave danger. La lutte contre cette endémie a connu deux périodes: la première periode de 1900 à 1938 est une phase de découvertes avec une tentative de lutte organisée en 1931, mais qui fut un échec; la deuxième période 1938–1945 fut plus fructueuse avec la création du Service général autonome de la maladie du sommeil qui parvint à circonscrire l'endémie. Plusieurs hypothèses ont été avancées pour expliquer la diffusion de la trypanosomiase pendant la période coloniale. On a mis en cause tour a tour la pacification et les déplacements de population. En réalité cette diffusion ne s'exerce que lorsque se produit des modifications profondes des milieux physiques et humains à la fois. En ce sens, la mise en valeur coloniale a joué un rôle de premier plan.

The study of migrant labour in Africa has tended to emphasize social form rather than historical context. This study of the immense migrant labour force that worked the Northern Nigerian tin mines is placed in the context of the ongoing subsumption of labour and existing social relationships by capital. Colonial conquest was required for the establishment of tin mining in Nigeria on a capitalist basis to serve the industrial needs of the West. Pre-colonial social organization prevented the release of sufficient labour for this purpose. After conquest, a migrant labour force was built up in conjuncture with a growing reserve army of labour by means of cash taxation, penetration of the market, weakening of slavery and state use of forced labour. In the second decade of the twentieth century there was substantial pressure from mineowners for the colonial regime to institute Rhodesian-style labour recruitment methods, but this was ultimately rejected because of the costs involved, the desire to encourage cash crop growth and the overarching aim of social stability. As a result, it was largely market forces which threw up the pool of labour that worked the mines, notably from the cash crop poor parts of Northern Nigeria and neighbouring French colonies. Initially, migrant labour was the most satisfactory option for many Northern Nigerian peasants, whose wages earned most in the pre-World War I era. The purchasing power of a miner's wage tended to decline, but social forces continued to throw up cheap labour. In World War II, the state instituted forced labour to mine tin, but the scheme was expensive, unproductive and opposed by business. The 1940s represented the nadir of worker poverty and the war was followed by a period of heightened social and political resistance to capital and the state. The tin mines both helped to cause and profited from the decay of the older mode of production in Northern Nigeria.

Erica Fiah's neglected life is a very valuable source of information on African political thought and action in colonial Tanganyika. His mission education imbued him with strong Christian values and a belief in British culture and civilization. Coming to Tanganyika from Buganda he was always rather alienated from the local society and culture, and was therefore inclined to seek a political and social community with educated Africans throughout the territory, or with the traders and workers in Dar es Salaam. He too would have liked to be the ‘Mwalimu’ of the Tanganyikan people. In his relations with the colonial government he clearly went a step further than Martin Kayamba or the African Association of his day, who relied on maintaining and exploiting the paternalism of the Government and its patron–client relationship with Africans. Fiah's attitude was one of ‘loyal opposition’, which he expressed first through his own Garveyite association, in the 1930s, and then through his newspaper Kwetu, during the 1940s. Fiah sought to improve and change the existing system, taking more active steps than mere petitioning to make the Government fulfil its moral obligations. This led him into conflict with the African Association in 1936–8; later it also distanced him from the emerging nationalist movement which he had helped fertilize, but whose complete rejection of colonial rule was beyond his intellectual horizon. Fiah's life was not the failure it seemed but a central link in the political transformation of the people of Tanganyika.