Urbanization in Africa: Some Spatial and Functional Aspects

The Joint Committee on African Studies held a second research conference on urbanization in Africa on November 12–14, 1970, at the Greyston Conference Center, Riverdale, New York. This subject has been a major concern of the committee for nearly a decade. Its first conference, held in April 1965, dealt with methods and objectives of research on African cities from a social and political view. (The conference papers were edited by Horace Miner and published as The City in Modern Africa.1New York: Frederick A. Praeger, 1967.)

The purpose of the November conference was to examine the spatial and functional aspects of African market centers and settlements, both large and small. Relatively few scholars are using this approach in study of African urbanization; of these, most are geographers, and a few are historians. This paucity of attention is surprising in view of the importance of these aspects of urbanization for national development in Africa.

For appraisal of methods and results of comparable research on other parts of the world, the committee invited participation by persons with experience in Latin America, China, and the United States—John Friedmann of the University of California, Los Angeles, G. William Skinner of Stanford University, and Brian J. L. Berry of the University of Chicago, respectively. The remaining participants, who prepared papers and served as discussants, had field experience in Africa in research relating to central places but not with spatial aspects as a focus.2Included, in addition to members of the committee and staff, were Gerald Breese, Princeton University; R. J. Davies, University of Natal; Allen M. Howard, Livingston College, Rutgers University; Peter F. M. McLoughlin, and Richard Stren, University of Toronto; Marvin Miracle, University of Wisconsin; J. Barry Riddell, and Robert H. T. Smith, Queen’s University; D. R. F. Taylor, Carleton University; and Thomas Boswell, Columbia University, and Martha Vill, University of Maryland (rapporteurs).

The conference papers dealt with the central place aspects of periodic markets, past centralities (Sierra Leone), small central places (Coast Province of Kenya), urban hierarchies (southern Africa), migration and diffusion in urban systems, and the overall structure of a space economy (South Africa). Theoretical and practical implications of research on these topics were examined in a final session. The papers treated both methods and substantive results of research. The results were preliminary and tentative in studies of tropical Africa and more conclusive in studies of southern Africa. This reflects the relative state of development of the countries under study and the availability of appropriate data. It also indicates that tropical Africa is the area of highest priority for continued research.

Periodic markets

In recent years there has been controversy concerning the relationship of periodic marketing to the propositions of central place theory, which is essentially addressed to an understanding of the location, size, and rank of market and service centers.3The basics of central place theory were laid out by Walter Christaller in 1933 and August Losch in 1941. Their works are available in translation: Christaller, The Central Places of Southern Germany, trans. C. Baskin, (Englewood Cliffs, NJ: Prentice-Hall, Inc., 1966); Losch, The Economics of Location, trans. W. H. Woglom and W. F. Stolper (New Haven, CT: Yale University Press, 1954). At the conference, Robert H. T. Smith discussed these problems.

Periodic markets are a basic institution for exchange of goods in Africa. Their distribution and functions can be explained within the framework of central place theory. Periodic marketing is identified as the situation in which sellers are faced with demand so low that they cannot achieve viable full-time operation at one site. Part-time marketing is one way to reduce the time cost to the trader; another is mobile marketing, in which the trader can expose his goods to a number of customers sufficient to keep him in business. Smith examined three hypotheses of periodic markets: the trader hypothesis, that market periodicity and location are arranged to minimize the trader’s costs; the welfare hypothesis, that the customer’s access to market is maximized through space and time; the local hypothesis, according to which the time interval for the market is worked out in relation to local social and economic conditions. The testing of these hypotheses he has found difficult. Evidence favors the welfare hypothesis but there is much unexplained variation.

There is differentiation among markets in the variety of trading activities involved. Hierarchies of markets and range of goods are clearly shown only in the context of unit of sale. For example, cloth, which is offered in most markets, is handled wholesale in an Ibadan market every 16 days and in a Lagos market every 32 days. These cases indicate hierarchical tendencies.

G. William Skinner, who has done extensive research on the development of marketing and market towns in China, in discussion of Smith’s paper questioned the suitability of the African scene for the study of periodic marketing because central place systems there are recent developments and in flux; the examples presented were from diverse cultures and introduced variables so complex as to make comparison difficult if not impossible. He asked about the relationship between market periodicity and population density. During the general discussion it was noted that this relationship is not linear. There may be a tendency for an increase in population density to be accompanied by an increase in market frequency within the same society. The societies of West Africa are undergoing increasing commercialization but at different rates. Skinner noted that long periods of time, often centuries, are needed for development of central place systems, and suggested that increased efficiency of transportation might be associated with increased frequency of markets.

Past centrality: Sierra Leone

Centralization has many bases in addition to marketing, although this is commonly dominant. Allen Howard examined centralities in nineteenth-century Sierra Leone, where towns seldom included more than 1,000 people and the volume of trade was slight. The basis of centrality at its simplest was a compound headed by a “big man,” who exacted produce as tax or tribute in this largely premoney economy. Collected produce was redistributed among clients and traded or used in external political negotiation.

The volume of trade among these small, multiethnic, and multilinguistic communities increased during the nineteenth century. The role of trader was of mutual interest to diverse groups. Traders working away from home were “strangers.” “Big men” and chiefs, regarded in this context as “landlords,” provided facilities for trading by these strangers. The facilities provided became complex when landlords collected goods for the traders, or in some cases provided credit. In the late nineteenth century long-distance trade routes were maintained in safety by means of cooperation among powerful political groups that shared interests in trade along the routes.

Political systems involved hierarchical relationships among compounds and groups of compounds, in towns. In some places, town-based chiefs or war leaders made important decisions for people of the surrounding villages, heard disputes, and dispensed justice. In many cases the towns were not unified politically but had competing factions; the system worked because the competition was largely peaceful. As trade increased there was a common dislike of anything that interfered with it.

Howard presented a map showing the distribution of major towns and their areas of influence during the 1860–90 period. He had tentatively ranked the towns by functional importance. Those of highest rank were found to have (1) many “big men” with wide connections, (2) military authority that provided control of the region, (3) domination of regional trade in one commodity or considerable importance in a few, (4) linguistic and ethnic diversity, and (5) location on a major transportation route. As colonial administration penetrated the interior, some previously important places lost functions; others, selected as bases for the new administrative hierarchy, gained. Penetration of the interior by rail and road caused further changes.

Small central places: Coast province of Kenya

A report by D. R. F. Taylor dealt with methods used to study central places in the Coast Province of Kenya, current problems of development there, and the Kenya government’s 1970–74 development plan for the area. To establish a data base from which to assess the relative prospects for growth of the central places in the Coast Province, Taylor and his associates during 1969 gathered information on the number and types of commercial, administrative, educational, medical, and other services available; data on volume of business or other transactions, where obtainable; measures of trade or service areas; traffic flow data; and information on past growth. Analysis of these data was not complete, but Taylor presented tentative conclusions: The Coast Province is predominantly rural with little centrality away from the few towns and the one city, Mombasa. The few places offering services were established in the colonial era. Demand for commercial services among the predominantly subsistence cultivators is not sufficiently high (the threshold notion) to sustain additional service centers. There is, however, demand for educational and medical services provided by the government. Service areas of existing central places are small, usually having a radius of 5–10 miles. The economic base for generation of local income to support additional development and more central places could come from agriculture and tourism. At present the coast is not a significant source of surplus agricultural production, but tourism is booming.

The Kenya government, troubled by overconcentration of people and resources in the cities of Nairobi and Mombasa has preached, “Back to the land,” but with little success. Under the 1970–74 development plan the government is attempting to correct this imbalance by arranging infrastructural investment in a hierarchy of places that it is hoped have potential for growth. At present, Nairobi and Mombasa have 70 percent of the urban population of Kenya. Nakuru, the third largest town, is less than one seventh the size of Nairobi. Some ten more towns have populations of over 6,000. Taylor suggested that the proposal under the development plan to set up a four-tiered hierarchy of places is not feasible in this area and that, instead, a set of very small centers should be developed. In discussion by the conference participants, the government plan was described as an action plan with an inadequate data base. The essential difficulty was that it used a model for structure of settlements (including the four-tiered hierarchy) that probably is not suitable for the Coast area. This question of suitability of model was raised repeatedly.

Migration and diffusion

Barry Riddell discussed the spatial aspects of migration and diffusion in emerging African societies. The new cities and towns are a frontier but one spatially quite different from the word’s usual connotation, based as that is on nineteenth-century American experience. The African frontier is punctiform, hierarchical, and discontinuous. The city is the point of contact between modernizing influences and African traditions. The cities are islands of modernization within large areas of traditional culture.

Geographic space is structured in any society by webs of social and economic interaction. Tribal, peasant, and modern societies each have characteristic spatial structures of transactions among people. Present geographic space in Africa is defined by growing lines of transportation and communication.

Migration within African societies is complex, reflecting many forces that motivate movement by individuals and families. Towns have become a major focus of migration while inducing still further movement. There is an element of feedback in the case of early migrants to towns who visit their home villages and tell of the attractions of town life. One pattern of migration to cities is that by steps, rural residents may move first to small towns, then to larger ones, and finally to the primate city. Small towns in such cases serve as stations for training in the ways of townsmen.

A characteristic of societies undergoing modernization is a rapid diffusion of innovations from the centers of innovation to distant recipients. The spatial routes of diffusion appear at first view sporadic and disordered. If, however, they are mapped on a base in which linear distance is transformed so that proximity is determined by social and economic similarities, then the routes of diffusion are seen to be systematic and direct from cities to smaller towns and eventually to isolated rural areas. This mapping of the functioning urban system shows diffusion moving down the steps of the urban hierarchy. Today’s functioning hierarchies are to a considerable extent superimposed on those of administrative centers that date from the colonial era.

In discussion William O. Jones questioned whether urban places are always the main centers of innovation and diffusion; it was his view that the European farm in Africa has been a more important center of diffusion of agricultural techniques than the town.

Urban hierarchies: Southern Africa

R. J. Davies of Natal examined the functional base of urban hierarchies in the Republic of South Africa, Lesotho and Swaziland, and the Transkeian Territorial Authority, which are areas at different stages of social and economic development. For each urban place he had compiled a list of central functions. This list was reduced by grouping similar types of commercial establishment; the functions were given relative weights according to their contribution to development; for each central place a centrality index score was computed.

The population of each South African urban place, excluding metropolitan centers, was then plotted against its number of functions. Davies found that breaks in the slope of the resulting curve gave five classes. Further plots of population against the centrality index scores again gave five classes of central places—“major country towns,” “country towns,” “minor country towns,” “local service centers,” “low-order service centers.” He then considered the ratio of the number of places in each class to the number in the class above and that below and found the ratio of the number in each rank of the hierarchy to the number in the rank above to be closest to three. That is, there are three country towns for each major country town, three minor country towns for each country town. This according to Christaller’s marketing principle is the appropriate ratio for market towns developed on a rural landscape. Davies suggests that while today the city system underpins an industrial economy, the ratios may represent a structure inherited from preindustrial phases of development. In the cases of Transkei and Lesotho, largely rural areas with little market development, he finds a ratio of seven: for each minor country town there are seven local service centers. This is in accord with Christaller’s administrative principle. Davies suggests that forces associated with imposed administrative and social services have played a greater role in development of the system than economic forces.

Structure of a national space economy: South Africa

T. J. Denis Fair, who had participated in planning the conference but was unable to attend, had prepared a paper with his collaborators, Christopher Board and R. J. Davies, which was presented by the latter. Discussion of the structure of the spatial economy was based in part on the foregoing analysis by Davies of the hierarchies. The Fair paper treated the contemporary national and subnational structure of South Africa in terms of economic surfaces of differing character and strength representative of the underlying formal regional landscape, the economic level of differing nodes within the surfaces, and the network and flows of telephone calls, labor migration, and road, rail and air traffic. Together these depict the spatial structure that is both formal and functional in character. One of the objectives of the study was to provide background for possible rational formulation of national development policy in the context of building on or altering existing regional structures.

Data on economic surfaces were gathered in terms of gross domestic product per square mile for administrative districts, and in terms of “welfare” of inhabitants, encompassing gross domestic product per capita, and “quality” of population in terms of education, age, and employment characteristics. A measure of welfare was obtained from a principal components analysis of 15 variables. Economic and welfare surfaces were mapped for the country. The “high” surfaces occur preponderantly in the northeast and coincide with the major metropolitan, industrial, and mining areas. They account for almost 72 percent of the country’s gross domestic product. Differentiation between surfaces is greater in the eastern half of the country than in the western.

The nodal structure which underpins the spatial economy is that of a principal metropolitan center—the Witwatersrand city complex—supported by a graded system of subnational centers resting on tiers of cities and towns of lower order. The subnational centers are sufficiently widely spaced that 60 percent of the country lies within 150 miles of these centers. Beyond this distance, nodes of a smaller order service the rural areas. As evidence of national linkage, movement of passengers on the national domestic airline, rail freight movement, and intermetropolitan telephone traffic were shown on maps. Subnational flows were shown on maps of telephone traffic between major cities and their hinterlands, newspaper circulations, and road traffic. These subnational flows indicate the nodal nature of the dispersed metropolitan centers.

The basic pattern of the space economy which emerged from the authors’ analysis is that of a principal region representing the most highly organized segment of the South African economy with levels of economic activity and spatial integration falling away from the main nodes. Other less complex regions also emerged, viz., the Western Cape with a Capetown node, and the Eastern Province with nodes centered on Port Elizabeth and East London.

The nature of urbanization

At the final session of the conference John Friedmann discussed theoretical aspects of the research on African urban systems that had been reported and some broad problems in the study of urbanization. He defined the basic characteristic of “urban” as the innovations that develop from nonagricultural ways of making a living. Innovations in writing, science, banking, mathematics, and industrial or commercial technology are all urban phenomena. In a setting of subsistence agriculture or nomadic herding, this type of innovation is or has been of minor importance. The influence on human settlement of diffusion of “urban” innovations from one urban area to another and from urban areas to rural areas has been widespread. Among the more visible effects has been a sort of urbanization of the countryside to the extent that urban phenomena, such as buses, are found in nonurban areas. The probability of innovation, however, is greater in urban areas. Friedmann’s questions were: “Is development possible without cities? Does development imply urbanism?”

A primary problem in research on urbanism throughout the world has been the unit of observation for the collection of data. Traditionally this unit has been the central place. Friedmann asserted that focus on central place does not facilitate exploration of power relationships between core area and periphery, which have been important in the underdeveloped parts of the world. Neither does it allow examination of political implications of economic dependency of one area on another. (Brian J. L. Berry earlier had stated also that central place theory is largely a theory of marketing and does not explain many aspects of centrality in underdeveloped areas.) Friedmann suggested that labor market area and potential urban field are probably useful units of observation. He noted that when such units are used small places lacking these attributes are eliminated, and the focus of study shifts to large places. This may be appropriate if development is a major concern of the study.

Further research on urbanization in Africa and elsewhere should be focused on process rather than structure. Among the processes requiring study are migration, flow of decisions, capital and information, and the diffusion of innovations. As better understanding of these processes evolves, the study of structure can be carried further. The effects of political and economic power on an urban system are immense. To a large extent the urban system is shaped by their influence on behavior. The developmental potential of areas within the urban system is constrained or facilitated through such influence.

Friedmann urged caution in the use of Western theories in a non-Western context and observed that social scientists have struggled to fit their data to Western theories.

Some summary reflections

Controversy about the applicability of central place theory to Africa and considerable clarification of the problem continued in the general discussion and in correspondence following the conference. Taylor observed that there is agreement that central places exist but not that they constitute a spatial system that can be ordered. Hierarchies exist but are troublesome to deal with, in part because of lack of data concerning the functional economic relationships.

The view of existing spatial systems is confused because in most cases several coexisting systems have developed from differing bases and are often not functionally integrated. Traditional systems were supplemented during the colonial era by a hierarchy of new administrative centers. In many cases these were the first towns on previously rural subsistence landscapes. These new towns had little commercial function; the local population continued to use periodic markets. The systems did not readily integrate. In other cases where the transition from subsistence to cash economy has been rapid, sets of central places in which to carry out market and service functions have emerged. These functions may be grafted on to towns which were previously administrative centers.

Were we to compile a thematic atlas of ignorance of the spatial aspects of urban systems in Africa the result would be salutary and disturbing. Some useful information on southern Africa exists, but information on East and West Africa is much more fragmentary.

In addition to the need for research on ongoing processes in the urban system already mentioned, the conference demonstrated that further study of functional integration within systems and its lack in coexisting systems is essential. Study of systems of centrality based on religion, administration, and communication would be rewarding. Within African urban systems the function and role of the primate cities, the major centers of innovation, are not adequately understood. Understanding of these functional-spatial parameters of African urban systems by scholars and administrators might well contribute to lessening the chaotic nature of African urban development.

The author was chairman of the group invited by the committee to plan the conference reported on here; the other members of the group were T. J. Denis Fair of Witwatersrand University, and Edward Soja of Northwestern University. The members of the joint committee, in addition to the author, are Elizabeth Colson, University of California, Berkeley (chairman); L. Gray Cowan, State University of New York at Albany; Philip D. Curtin, University of Wisconsin; William O. Jones, Stanford University; Igor Kopytoff, University of Pennsylvania; Roy Sieber, Indiana University; and Robert F. Thompson, Yale University; staff, Rowland L. Mitchell, Jr.

Walter W. Deshler, professor of geography at the University of Maryland, was a member of the Joint Committee on African Studies, which is cosponsored by the Social Science Research Council and the American Council of Learned Societies.

This essay originally appeared in Items Vol. 25, No. 3 in September 1971. Visit our archives to view the original as it first appeared in the print editions of Items.