The study of the history of Africa during World War I raises two major problems of synthesis and a host of smaller problems. First of all, the sheer diversity of the continent and the extremely uneven nature of its precolonial development, let alone the patchy and differentiated modes of imperial and colonial penetration, make it difficult to see its experience, even of so ostensibly cataclysmic an event as World War I, as a unified whole. Indeed, the diversity of the continent was mirrored in the diversity of its experience of the war, which combined the actual agony of the battlefield for many thousands of black troops both in Africa and in Europe at one extreme, with the undoubted uneventfulness of those same years for many others.

World War I marked the final phase of French colonial expansion. France's African war aims were determined not by the cabinet but by the leaders of the colonialist movement and by a handful of African enthusiasts in the colonial and foreign ministries. Most of these men harboured the unrealistic aim of acquiring not merely German territory but also other foreign ‘enclaves’ in A.O.F. At the peace conference, however, France's African gains were limited to mandates over the greater part of German West Africa.

Before August 1914 no government had given serious thought to the potential contribution of French Africa, either in men or raw materials, to a war in Europe. The enormous losses on the Western Front led to the recruitment of French Africa's first great conscript army. By the end of the War French Africa had sent 450,000 soldiers and 135,000 factory workers to Europe. The crisis of French food supply also led in 1917–18 to the first concerted campaign, mounted jointly by the colonialists and the colonial ministry, for the mise en valeur of the Empire. But France's shipping losses made it impossible to increase her African imports.

In the aftermath of victory French Africa appeared genuinely popular in France for the first time. The main reason for that popularity was the naïve belief that the resources of the Empire would free France from dependence on foreign suppliers and speed her post-war recovery. When the resources of the Empire proved even slower to arrive than reparations, the Empire quickly lost its newfound popularity. The War nonetheless left behind it the myth of the Empire as a limitless reservoir of men and raw materials: a myth which, though dormant for most of the inter-war years, was to be revived by the coming of World War II.

When the French government introduced military conscription into the A.O.F. in 1912, the Guinean colonial authorities saw the measure as a means of training a local administrative corps to replace the traditional chieftaincy, through whose military defeat the conquest of Guinea had very largely been effected. However, the chiefs had by no means disappeared by 1914, and wartime demands for recruits were too massive to be supplied without their assistance. Their help was bought with promises to consolidate their authority in peacetime. Although able to marshal recruits, the chiefs seem to have been unable to prevent large-scale desertions before the moment of embarkation for France; village populations could also avoid conscription by overland migration out of the A.O.F. The colonial authorities therefore felt constrained to offer substantial inducements, mainly concerning improved social status vis-à-vis the chiefs, to the individual recruits. These contradictory policies were compounded by the recruitment drive of Blaise Diagne in 1918, which involved a further promise to recruits of improved status vis-à-vis the French authorities. The return of ancien combattants to Guinea was marked by outbreaks of strike action among workers in Conakry and along the railway line; by riots in demobilization camps; and by rejection of or agitation against chiefly power in the home cantons to which they dispersed. The anciens combattants did not form a coherent or organized political movement, but remained a conspicuous social grouping between the wars. Although they appear to have been strongly influenced by their experience of war and by contact with French socialists, their conflict with the chiefs seems to have counted for more with them than any confrontation with the French.

Although on the periphery of the war Gold Coast resources and manpower were mobilized for the imperial war effort. The educated élite and many traditional rulers were loyal and internal conditions, despite the withdrawal of personnel and troops, generally peaceful. Small-scale disturbances occasioned by the war occurred, the most serious in the Northern Territories. The direction and pattern of Gold Coast external trade changed; exports, with the exception of cocoa, contracted and the price of imports rose. Serious shipping shortages exacerbated difficulties. British ‘Combine’ firms increased their hold over Gold Coast commerce. A fall in government revenue held up public works, and railway construction was paid for by an export duty on cocoa. The war brought marked changes to the government fiscal system. Gold Coast troops were used in the West and East African campaigns and prepared for employment in the Middle East. Varying degrees of compulsion were used to recruit carriers and soldiers and resistance to this was widespread. Labour shortages and the withdrawal of whites provided new job opportunities for Africans. Cocoa and palm kernels were subject to imperial direction and control; Governor Clifford opposed the imperial preference scheme for palm kernels. Imperial wartime economic measures fuelled the nationalism of the NCBWA; the Gold Coast élite demanded political representation as a reward for wartime loyalty, while their economic resolutions attempted to displace European commercial interests strengthened during the war. Economic changes further weakened the position of traditional rulers; labour shortages provided wage labour with temporarily enhanced bargaining power. Post-war trouble from ex-servicemen was slight.

In 1916 the South African government received a request from the Imperial government for the provision of non-combatant African labour for work in France. Despite opposition from white opinion on both political and economic grounds, the South African Native Labour Contingent was formed and recruiting commenced. Although recruiting had the active support of African political leaders, it was not as successful as had been hoped. Distrust of the government's intentions was one important reason for this. The South African government had agreed to the Imperial government's request for labour only on the condition that S.A.N.L.C. units were to be kept segregated from both other military units and the French civil population, and numerous measures (particularly the construction of compounds) were devised to facilitate this. But in practice this proved impossible to implement properly, and South African officers did not have the degree of control over their units that had originally been envisaged. On the African side, there was a considerable amount of dissatisfaction with conditions, and in one incident thirteen Africans were shot dead by their own officers. When the South African government decided to bring the ‘experiment’ to an end early in 1918, many Africans suspected that the reasons for this were not purely military as was claimed. Service in the S.A.N.L.C. was of importance both in terms of the individual experiences of those Africans directly involved, but it acquired also a wider political and symbolic importance, attached particularly to the sinking of the transport, S.S. Mendi, in February 1917 with the loss of over 600 African members of the S.A.N.L.C.

During World War I, Africans in Nyasaland were called upon to provide large numbers of soldiers and military labourers for the war effort in eastern Africa. Although a few willingly volunteered, many more objected, and some resisted. In this situation, colonial officals used force to secure the necessary manpower. Africans, therefore, called the conflict ‘the war of thangata’, referring to the growing colonial demands for taxes and for labour rent on European estates. The tasks which the soldiers and carriers were called upon to perform were equally likened to thangata, being ‘work which was done without real benefit’. So far from receiving rewards, Africans found that inadequate food, clothing, and medical care contributed greatly to the sufferings associated with a military campaign. Between 1914 and 1918 wartime manpower requirements, and war service, gave full meaning to colonial rule throughout the protectorate. The response to these demands and this suffering brought, in the form of both traditional and modern religious and social institutions, the first tentative stirrings of African nationalism in Nyasaland.

For the campaign in East Africa from 1914 to 1918, the British used over 50,000 African troops, and over one million African followers. In 1914 no carrier organization existed, so this had to be rapidly improvised. There were three main carrier forces, based on the East Africa Protectorate, on Uganda and on Nyasaland and Northern Rhodesia. German East Africa was overrun in 1916 and 1917, but the German forces were not defeated. These offensives necessitated huge numbers of followers. Despite much improved rations and medical services, deaths among followers averaged 10 per cent; over 100,000 must have died. Over 10,000 troops died of disease or were killed, a death rate of 20 per cent. Deaths were most numerous amongst those followers who served for long periods far from home; this applied particularly to those from the East African Protectorate. About half of the million followers were, however, on short contracts or were casual labour. Since they worked nearer home and for shorter periods, their death rate was much lower. During 1916 the carrier force from the East African Protectorate was reinforced from conquered parts of German East Africa, but diminished by 100,000 men through releases, desertions and deaths. Numbers reached a climax in 1917, with the mass levy. The possibility that men enlisted more than once is hard to prove, but long-service carriers on release were unlikely to be fit again for a long time. Many recruits were medically unfit for the mass levy of 1917. During the war very many of the able-bodied male populations of these territories must have served, probably over 80 per cent, but not all at any one time. As it was the main theatre of war, German East Africa probably suffered most, conscriptions being carried out by both Germans and British.

It has usually been supposed that World War I was ‘an injury to the Christian cause’ because of the disruption of missionary work when mission personnel were called up, interned or not replaced. This view is questioned. Evidence is adduced from the history of the church in East Africa to show that African Christians responded to the situation by shouldering responsibilities in a way which surprised the missionaries on their return. The churches best placed to survive were those in which a beginning had been made to train African clergy. Only the Anglicans and Catholics had made any progress in training indigenous leadership by 1914. But even where this had not been done, leaders emerged, and some churches even grew considerably in numbers without any loss of quality. One example of this is drawn from the Usambara–Digo synod of the Lutheran Church in Tanzania. The missionaries' attitudes and actions on their eventual return are surveyed. Often they were surprised to find that in their absence the Christian communities had not disintegrated as they had feared. But almost always their concern was to ‘discipline’ the church, and return to the ways of doing things at the outbreak of war, instead of building on the developments which had occurred in the meantime. This sometimes had disastrous consequences as natural leadership became frustrated. The greatest ‘injury to the Christian cause’ may have been the missions' failure to see that a new method of working was now required of them rather than a return to the old.