AFRICA'S PLACE IN GLOBALIZATION: AFRICA, EURASIA, AND THEIR BORDERLANDS

AFRICA'S PLACE IN GLOBALIZATION: AFRICA, EURASIA, AND THEIR BORDERLANDS
Patrick Manning
Africa is commonly marginalized in global social studies, whether of present or past. This essay makes the case for the substantial importance of Africa through a systematic comparison with Eurasia. It documents the large area and the relatively dense population of Africa, in past and present, as compared with Eurasia and also with the Americas. The essay gives particular attention both to sub-Saharan Africa and to the long Afro-Eurasian borderland from Gibraltar to the Bab al-Mandab, and briefly explores the interactions of Africa, Eurasia, and their borderland since the beginnings of humanity. In the course of the comparison, the essay raises the question of whether the theory and methodology of historical globalization studies need to be more fully specified in order to ensure inclusion of the African region and perhaps other historical situations that have been insufficiently represented in the understanding of globalization.
Keywords: globalization, Africa, history, Eurasia, Afro-Eurasian, interaction, comparison, population, periphery, borderland.
Introduction
Where is Africa in studies of globalization? This essay argues that globalization studies should focus more attention on Africa and Africans, on the specific characteristics of African societies, and on the relationships between Africa and Eurasia. Africa and Africans - a large terrain and a large population - continue to be treated as marginal in world affairs today, and continue to be treated as marginal in global historical studies. Some adjustments have come recently to this marginalization as a result of the past century's global critiques of imperial hegemony and racial categorization, along with the rise of independent African nations. These same factors, along with confirmation of the African origins of all humanity, have led also to revisions in historical studies. In one such revision, the term 'Afro-Eurasian' has developed as a descriptor of the framework for long-term social interaction. In practice, however, 'Afro-Eurasian' analyses address only a portion of Africa, so that the question of Africa's marginality is not really resolved.
This essay reconsiders the relative neglect of Africa in contemporary global affairs and in historical studies. While the relative weakness of Africa in global politico-military affairs must be acknowledged, I argue that Africa is of substantial significance at a global scale by other measures - first in history, and by implication in current affairs. The point of this comparison of Africa and Eurasia is not to argue that the two great continental regions are equal or even fully parallel, but that a detailed comparison of the two regions is instructive.
I present my comparison of Africa and Eurasia as a historical study in globalization. The premise of historical studies of globalization is that globalization did not suddenly
Journal of Globalization Studies, Vol. 5 No. 1, May 2014 65-81
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appear ex nihilo at the end of the twentieth century: contemporary globalization was preceded by historical globalization. Our common task is to find other sites in time, space, and population that reveal the character and the historical trajectory of processes of globalization (Hopkins 2002; Chase-Dunn 2006; Chase-Dunn and Hall 2012; Gills and Thompson 2006). In this work, I argue, we should pay close attention to the definition of globalization and to the procedures adopted for historical study of globalization.
My main line of argument is empirical, but I wish to begin with a brief commentary on issues in theory and method. The marginalization of Africa in social analysis began long before studies of contemporary and historical globalization took form, but globalization studies have not yet succeeded in challenging that marginalization. As a result, I believe that there is need for revision in the theory and methodology of studies in historical globalization so as to provide systematic encouragement for inclusion of Africa in the analysis. Such revision might lead to other benefits for globalization studies. Historical globalization is defined most broadly as large-scale processes and connected processes in the past (Hopkins 2002). In practice, this has brought more attention to the symptoms of globalization than to its underlying dynamics. For instance, the initial characterization of historical globalization by Hopkins and Bayly was symptomatic: they proposed 'archaic globalization' and 'proto-globalization' more as periods of time rather than as mechanisms (Hopkins 2002; Bayly 2004). To inquire into the dynamics of globalization, I begin by arguing that globalization should refer to social change, but not just any type of social change. Social change, in order to count as globalization, must be substantial in magnitude, must affect a broad geographical region, and must occur rapidly. But how much of each? The growing literature now in print on episodes of globalization in history has naturally assumed that a historical process may qualify as globalization even it the social change was not fully planetary, nor instantaneous, nor of completely revolutionary magnitude (Hopkins 2002). But what processes of change count as globalization? Can the impulse to globalization be exogenous as well as endogenous? For instance, can the response to such an exogenous change as the sudden climatic change as the Younger Dryas cooling episode (12,000 years ago) be seen as globalization? For socially endogenous change, should we give separate consideration to the initiation and the propagation of change? Does the change take place in one spot and then spread by diffusion? Does the change take place system-wide? Is the expanding scale of globalization irreversible, or is globalization followed sometimes by 'de-globalization' ?
In addition to defining the nature of past globalization, we face the question of how best to study it. While globalization is about the world as a whole, it is difficult in practice to analyze the whole world at once. One ends up selecting sites that appear to be central to the processes of globalization or appear to lend themselves particularly to understanding how those processes work. Yet by selecting eclectically we risk replicating inherited narratives of civilizational hegemony rather than conduct innovative and critical sort of social analysis. We should be cautious about focusing our attention on the same centers and heroes that have been the high point of so much past celebration of empire and civilization. Do certain populations encompass key elements of globalization? Is it best to rank populations by GDP, either aggregate or per capita? By the nature of their interactions with each other? Do we analyze sites in isolation, on the assumption that globalization results from episodes of invention within centers of wealth? Similarly, do the magnitude
of cities, states, and armies provide the best indices of globalization? Can we also seek to trace interconnection of sites, to see if their connections bring innovations?
The present study focuses on a critique of the marginalization of Africa and Africans both in current affairs and in historical analysis. The stages of this essay make the case for greater attention to Africa in the study of global change and review the typology of episodes in globalization. Part 1 makes the case that Africa is more important today than commonly realized in area, population and other measures. Part 2 presents several alternative spatial frameworks for considering Africa and Eurasia separately and together. The point is not to argue that there is one best spatial framework, but that the various frameworks have strengths and weaknesses which, properly deployed, can improve global analysis. Part 3 presents a rapid, long-term review of the interplay of Africa and Eurasia, with particular attention to the long borderland connecting the two continents. At the conclusion of these relatively straightforward exercises, I argue that attention to the macro-dimensions and interactions of Africa and Eurasia will lead to better understanding of Africa itself, better recognition of Africa's past and present in the world, and better understanding of which instances of past social change qualify properly as globalization.
Africa in the World Today
Area and population
I begin with a crude comparison of the geographic areas and population sizes of the three largest continental units: Eurasia, Africa, and the Americas, along with Oceania. Table 1 gives commonly cited figures for 2010. The first point is that Africa is relatively large in area: it is 55 per cent of the area of Eurasia, and over 70 per cent of the area of the Americas. Second, Africa is very populous. A simple way to sum up current world population is to note that we have a total of seven billion humans, five billion in Asia and one billion each for Africa and the Americas. If we break Eurasia up into regions, we can say that there is just over a billion in East Asia, well over a billion in South Asia, just under a billion in Europe, and just over a billion spread around Southeast, Central, and West Asia. Africa, in aggregate population, is roughly the equal of each of these units. Third, Africa is relatively densely populated. African population is currently 150 per cent that of the Americas; it is just under 40 per cent of the Eurasian population density. (A simplified version of this calculation would be to say that Africa has half the area of Eurasia and one fifth the population of Eurasia, so that the African population density is two fifths that of Eurasia.)
The large and barren regions of each continent, when considered explicitly, bring even more attention to Africa. The Sahara, with an area of over nine million square kilometers and a population of four million, is nearly one third of the area of Africa. Siberia, over 13 million square kilometers in area and with a population of 40 million, is a quarter of the area of Eurasia. Canada and Alaska, with an area of 10.5 million square kilometers and a population of 36 million, are a quarter of the area of the Americas. Thus, leaving aside the Sahara, Siberia, and Canada/Alaska, the population density of Africa is calculated at 70 per cent that of Eurasia and over twice that of the Americas. As important as the size of these barren areas is their location: the Sahara and the Arabian Desert are located right in the middle of an otherwise densely populated region, while the arctic regions of Eurasia and North America are relatively isolated.
The Sahara is the greatest terrestrial obstacle to communication among populated regions - in this sense it is paralleled only by the Himalayas and the Taklamakan, separating East Asia from Central and South Asia.
Table 1
Continental area, population, and Gross Domestic Product, 2010
2010 Area (10s sq km) Population Pop Density per sq km GDP $US million
Eurasia 55 40.6 % 4,902,451,000 71.1 % 89.1 31,020,420 56.4 %
Africa 30 22.1 % 1,022,234,000 14.8 % 34.1 1,610,887 2.9 %
Americas 42 31.0 % 934,611,000 13.6 % 22.3 20,929,832 38.1 %
Oceania 8.5 6.3 % 36,593,000 0.5 % 4.3 1,392,987 2.5 %

World 135.5 100 % 6,895,889,000 100 % 54,954,126 100 %
Source: United Nations 2012.
Levels of economic output tell a different story than area and population. As indicated in Table 1, African GDP is under three per cent of the global total - five per cent of the Eurasian total and eight per cent of the total for the Americas. Figures such as these help explain why Africa is often forgotten in global affairs. But suppose we compared on the basis of caloric intake? We lack adequate comparative figures for caloric intake, but let us try some hypothetical figures to get at least a hint of the relationship. If we assumed that per capita caloric intake per day in the Americas were 3200 calories, and that the equivalent figures were 2800 calories for Eurasia and 2200 calories for Africa, then we would estimate that Eurasia consumes 72 per cent of calories, Africa consumes 12 per cent, and the Americas consume 16 per cent (Livestrong 2013). And since caloric intake is roughly equal to energy output, this calculation - however rough - is a reminder that a great deal of human energy is being output in Africa.
Is the relative density of African population a brand new phenomenon? It is known that African population has been growing at a high rate - over two per cent per year since 1950. Commonly available figures suggest that African population was very sparse until the mid-twentieth century. Recent research, however, suggests that African population was historically rather dense and has grown slowly. Fig. 1 provides an overview comparing estimated continental populations since 1600. These figures show stagnation in African population during the eighteenth and nineteenth centuries, especially because of the effects of slave trade, followed by growth in the twentieth century (Manning and Nickleach, forthcoming). For Eurasian regions, current estimates show steady growth over the long term. For the Americas, population declined sharply in the sixteenth and early seventeenth century, then began to increase, especially because of immigration from Africa and Europe. The overall result is that African population was over one sixth of the global total in 1600 and one seventh of the global total in 2010, but was a smaller portion of the global total in between those times.
1600 1700 1820 1950 2010
Fig. 1. Estimated continental populations, 1600-2010
Source: Maddison 2001: 231-241; Manning and Nickleach, Forthcoming; United Nations 2012.
Africa's regions
As an additional way to emphasize the large area and population of Africa, it is useful to consider the continent in terms of its major geographic, cultural, and political regions. Table 2 shows seven major African regions plus the Sahara, as compared with seven regions of Eurasia, plus Siberia. The African regions are somewhat smaller than the Asian regions, but they are quite large as compared with all but a few national units worldwide.
Table 2
Comparing regions of Africa with regions of Eurasia
African Region Area 10s sq km Pop. 10s Density per sq km Eurasian Region Area 10s sq km Pop. 10s Density per sq km

Maghrib 2.99 78 26 Western Europe 4.04 443 109
Northeast Africa 2.76 87 32 Eastern Europe 8.30 255 16
Horn 4.15 142 34 Middle East 4.54 231 51
West Africa 6.14 304 50 South Asia 6.78 1704 251
West Central Africa 8.99 126 14 Southeast Asia 2.90 593 205
East Africa 4.47 225 50 East Asia 11.80 1573 133
Southern Africa 2.69 58 22 Central Asia 3.99 61 15
Sahara 9.00 4 0.4 Siberia 13.00 36 4
Source: United Nations 2011, Mongabay 2013.
Further, one may distinguish African regions in terms of their major physical features. Thus, Northeast Africa and half of the Horn are drained by the Nile, about half of West Africa is drained by the Niger, and half of Central Africa is drained by the Congo. Southern Africa is drained by the Zambezi, the Limpopo, and the Orange. The Maghrib is centered on the Atlas Mountains, while East Africa centers on the mountains of the East African ridge and the Great Lakes.
Fig. 2. African regions and population density
Source: author. The African Web
Communication across the African landscape proceeds in many directions. Except for the Sahara, often a barrier restricting communication, it has been relatively easy to move in any direction. I have proposed the notion of 'the African Web' to suggest this network of communication in all directions (Manning 2009: 40). That is, while Africa had no Silk Road - no single great highway linking distant centers - it has had numerous, small-scale routes enabling people, ideas, and material goods to be exchanged in all directions. The colonial powers in Africa, focused mainly on extraction of raw materials, built railroads inland from coastal ports, declining to link inland areas with each other, so that the African Web was weakened during the colonial era. But the subsequent development of motor transport (even without adequate investment in roads) brought the African Web back.
Spatial Frameworks Including Africa and Eurasia
The relationships between Africa and Eurasia can be portrayed in various ways, and the various portrayals point to contrasting historical and social interpretations. This section compares six overlapping characterizations of the place of African space within the overall Eastern Hemisphere. These frameworks, in making explicit the underlying assumptions about the relationships of Africa and Eurasia, help clarify alternative hypotheses so that they can be documented and tested. They are as follows:
Africa as a Eurasian periphery
Africa as a world apart
o Continental Africa o Sub-Saharan Africa o Africa plus Arabia ... and Iberia
Africa as joined to Eurasia by an Afro-Eurasian borderland
Africa and Eurasia as a single great region
Africa as a Eurasian periphery
This is in effect Afro-Eurasia. This framework is beneficial in conveying an expanded Eurasian terrain, but it is problematic in that it leaves out of consideration the regions of densest African population.
Fig. 3. Roads, indicating Africa as a Eurasian periphery
Source: author. Africa as a world apart
In this framework, Africa is seen as a distinctive region, with its own commonalities and internal communication. Within this framework, one may assume distinctive peoples, social patterns, and histories; an economy organized in a distinctive fashion; and a distinctive ecological setting. Indeed, this is the framework within which multidisciplinary African Studies has developed. (Africa is just over one third of the eastern hemisphere in
area.) Within this framework, however, there exist at least three competing versions: all three of them are displayed in Fig. 4.
Fig. 4. Africa, with three northern boundaries
Source: author.
Continental Africa. First, and most commonly in contemporary analysis, is Continental Africa, bounded to the north by the Mediterranean and Red Seas, as indicated by the heavy dotted line. The problem with the focus on a distinctive Continental Africa is that it minimizes African relations with other, nearby regions.
Sub-Saharan Africa. This is the region south of the lower dotted line in Fig. 4. The distinction made in drawing this line is part ecological and part racial, though neither criterion is precise. Ecologically, the boundary between sub-Saharan and northern Africa is drawn as far south as the southern fringe of the Sahara and as far north as the southern boundaries of Morocco, Algeria, Libya, and Egypt. Drawing a racial frontier neglects the migration that crosses the Sahara in both directions: many black people live in northern Africa, and the overall color gradient shades gradually from south to north.
Africa plus Arabia. Since the ecology of the Arabian Peninsula is so similar to that of northern Africa, it makes sense in these terms to treat Africa plus Arabia as a unit. As with northern Africa, there has been substantial migration in both directions, and especially from Africa to Arabia. Further, Arabia and the lands to its north are mostly Arab in language and culture, are very similar to northern Africa. Put differently, the peoples of Arabia, Iraq, and Syria are mostly Semitic-speaking, and the Semitic languages have
their origins in Africa. The northernmost dotted line in Fig. 4 shows Africa plus Arabia, even including some trans-Mediterranean lands.1
An Afro-Eurasian borderland
Rather than shift among these three visions of the northern boundary of 'Africa', one can identify an 'Afro-Eurasian borderland' - a zone of interaction, mostly desert and sea. That is, the area in Fig. 4 between the two lighter dotted lands can be seen as a major zone of interaction between the African and Eurasian continental centers. This characterization echoes the more general attention that Hall has given to borderlands (Hall 2009).
Africa and Eurasia
More broadly, one may conceptualize an overall, hemispheric unit. In this case one may note the temperate lands of the northwest and the east, the great band of arid lands stretching across the hemisphere from Mauritania to Mongolia, and the densely populated tropical lands from Senegal to the Philippines. We may also note the band of dense population and elaborate socio-economic systems running between Iberia in the northwest and Indonesia in the southeast (the Afro-Eurasian borderland forms much of the western portion of this band).
My argument is that analysts should be explicit about which of these frames they are using when discussing either past or present. It is important to identify the purpose of each comparison and linkage among regions, and to use a spatial conceptualization that is consistent with the purpose.
Over Time: Africa, Eurasia, and the Afro-Eurasian Borderland
The separate and interacting histories of Africa, Eurasia, and their borderland provide examples of contrasting patterns of change. The compressed narrative in this section is
Fig. 5. The Eastern Hemisphere, showing climatic regions
intended to provide just enough information to show how the patterns differed. As I see it, the narrative should convey the varying types of change which contributed to historical globalization. These might include changes resulting from forces exogenous to human society, inventions at specific locations that were then diffused, independent inventions resulting from parallel inspiration, instances of interregional interaction - and perhaps, crystallizations of novelty that appeared throughout the hemispheric or planetary system. The summary of these changes is expected to provide information on early episodes of globalization, as contrasted with other sorts of social change.
Parallels, separations, and connections, 200,000 to 15,000 years ago Communities of Homo sapiens sapiens emerged in what is now Ethiopia about 200,000 years ago and remained overwhelmingly within Africa until out-migration began somewhere between 80,000 and 70,000 years ago. Modern humans were constrained within sub-Saharan Africa, especially during a long period of cool and dry weather from 190,000 to 130,000 years ago which made the Sahara (and Arabia) virtually impassable. Two fairly brief periods of warm and wet climate made it possible for these humans to enter and cross the Sahara, and remains of such migrants have been documented in Qafzeh cave in Israel, dated 100,000 years ago. But with the return to cool and dry weather, this population did not survive. Meanwhile, the Homo sapiens sapiens population experienced enough cross-community migration and interaction that those who emigrated from the African continent were typical of those remaining (Manning and Trimmer 2012).
From as early as 80,000 years ago, serious migrations beyond Africa began to take place, but only along the tropical shores of Asia. These migrants spread from South Arabia along the Indian Ocean coast all the way to Australia, New Guinea, and the Philippines. From the estuaries, some migrants moved up river valleys and found fertile tropical highlands - such as along the flanks of the Himalayas and in New Guinea -where their populations could grow in parallel to the lifestyle of African highlands. These tropical lifestyles were shared throughout the human habitat.2 Continued migration sustained contact among communities; equally importantly, humans everywhere sustained their common fund of instincts, habits, and intelligence.
Only as of about 45,000 years ago did communities of Homo sapiens sapiens reach temperate lands. The continuing aridity of the Sahara and of Arabia limited the routes north from the tropics, so that on present evidence Asian routes north seem to have been the most promising for learning to live in colder lands with temperate flora and fauna. That is, in this cool and dry era, the lands west of the Himalayas and east of the Caspian Sea were the most resource-filled path to the temperate grasslands. Those who migrated into the temperate zone, from a base that may have been in the Ganges Valley, were small in number but largely typical of those living throughout the African and Asian tropics. As they reached the temperate steppes and learned to hunt and gather in this very different environment, they were able to spread both east and west along the steppes: in this cool and sun-deprived temperate latitude, the superficial changes that we now call 'race' began to appear on human bodies. According to this reasoning, humans reached Europe and the Mediterranean by a route north of the Black Sea. That is, the Sahara, the Arabian Desert, and the Levant had remained very dry, so that contact between the Mediterranean and sub-Saharan Africa was rare indeed. Popula-
tions grew in each region of human settlement, yet it may be that the majority of human population remained in the ancestral homeland of sub-Saharan Africa
The Glacial Maximum, from 25,000 to 15,000 years ago, brought extremely cool and dry climate to every region, and made communication among regions even more difficult. Yet this era - along with the succeeding period of rapid warming beginning 15,000 years ago - was a time of extraordinary innovation in human society. In parallel developments throughout the hemisphere, humans made advances in constructing housing, in clothing, in ceramics, in domestication of animals, in fishing techniques, and in the intensive gathering of plants that eventually led to agriculture. In general, human communities made important moves toward reliance on production of their resources in addition to gathering. From 15,000 years ago a rapid warming brought expansion in the flora and fauna available for human exploitation. The warming continued, but not 11,000 years ago did the Sahara and the Arabian Desert become grassland dotted with streams and lakes. One more key punctuation of this transition was the Younger Dryas, a thousand-year era from roughly 12,000 to 11,000 years ago during which temperatures fell sharply. This cold snap, which surely brought deprivation in food supplies, is widely thought to have initiated the response of planting seeds, so that agriculture developed in several regions in succeeding millennia.
Turnabout: Linkage of Africa and Eurasia, 11,000 to 5,000 years ago The opening of the Holocene era, with its rapid warming, made possible connections across a verdant Sahara and Arabia, so that terrestrial communication of Africa and Eurasia became easier than at any time in the previous 80,000 years. Agriculture and animal husbandry were developing at three major loci within this newly fertile borderland: in the Levant, in the eastern Sahara, and on the flanks of the Ethiopian highlands. In addition, there is very strong linguistic evidence of substantial migrations from sub-Saharan Africa into the borderland, and the early Holocene is most likely the time in which that migration took place. That is, the Semitic languages of the Levant and Arabia, the Ancient Egyptian language of the lower Nile, and the Berber languages of the Maghrib all have their ancestry in the Afroasiatic languages which arose in the middle Nile Valley. Migrants from the middle Nile may have reached the Mediterranean fringe at the start of the Holocene, spread and settled among peoples east and west, and established the dominance of their Afroasiatic languages.
The wheat of the Levant and Egypt, the sorghum of the Sahara and the savanna, and the millet and teff of Ethiopia were each major developments of the early Holocene era. Climate change later in the Holocene gave great encouragement to the further expansion of wheat, yet sorghum not only expanded in the African savanna but also reached North China and thrived in that region. Cattle, sheep, goats, and donkeys were domesticated at various parts of the Afro-Eurasian borderland during the Holocene, and were shared throughout. Developments in use of fire brought creation of ceramics in the Sahara and later throughout the region.
Eurasian Shifts in a Divided Hemisphere, 5000 to 2000 years ago From just over 5000 years ago, global climate became somewhat cooler and, more importantly, entered a period of remarkable stability which continued up to the present. With the cooling, the Sahara and Arabia again became desert, thus reducing the ease of contact between Africa and Eurasia. At this moment arose a unique innovation that
turned the history of Eurasia in a new direction: the domestication of horses. Central Asian communities had developed warfare with horse-drawn chariots by 2500 BCE (4500 years ago), and after 2000 BCE chariot-led armies conquered territories from Egypt in the southwest to the Yellow River valley in the east. Horses encouraged military centralization, enslavement, and overall social hierarchy in region after region of Eurasia. Horses also crossed from northern Africa into sub-Saharan Africa, but sleeping sickness borne by tsetse fly greatly limited the social and military influence of horses in tropical Africa. Cowries spread throughout Eurasia and into the Mediterranean from the Indian Ocean, serving as currency along with silver (Yang 2011).
While Eurasian societies became distinctive in their development of large states, technical advances continued to unfold throughout the hemisphere. Advances in managing fire led to further innovations in ceramics and, as temperatures got higher, to various types of metallurgy, eventually including the smelting of iron, which is now understood to have been developed in several places in Eurasia and in Africa, all in the second or first millennium BCE.3 Connections along Indian Ocean shores remained feasible even as the deserts dried out: cotton, domesticated in Africa as an oil seed, reached India, where its fiber was developed; thereafter, cotton returned to Africa as a source of fiber.
Afro-Eurasian Borderlands from the Common Era to 1500 CE
While climate became marginally cooler and dryer, advances in human technology expanded the links of Eurasia and sub-Saharan Africa, notably by the beginning of the Common Era two thousand years ago. Camels, domesticated in Eurasia in the first millennium BCE, made it possible to traverse and inhabit the Sahara and the Arabian Desert. Waterborne trade along the Red Sea linked Egypt to East Africa as well as to India. While it is common to see these connections as representing a Eurasian penetration into Africa, one can also suggest that the Afro-Eurasian borderland reached prominence in this era by drawing on its own resources and also on more distant resources in each direction. The religions of Christianity and Islam (and others as well) developed within the borderland and spread in both directions. The literate culture of the borderland reached a particularly high level.
Sub-Saharan Africa, in this era, extended its distinctiveness from Eurasia by developing networks more rapidly than hierarchies. Modest-sized states developed throughout the continent, but it was also the case that the city of Jenne-jeno, on the Niger river, developed into a major commercial center without any central palace or hierarchical government (McIntosh 1995). Trade networks linked continental regions and crossed the Sahara, the Red Sea, and the Indian Ocean. A mature iron-age technology had spread throughout the continent, though in some cases shortages of firewood arose and limited metallurgical work (Brooks 1993).
The era from the tenth through the twelfth centuries brought a great set of religious struggles to the borderland. The Crusaders dispatched by the papacy to the Levant were the most prominent dimension of this struggle. But also to be included are the Almora-vid and Almohad conquests of the Maghrib and Iberia in response to early advances of the Christian Reconquista, Saladin's seizure of Yemen, and the religious wars of the Horn of Africa, which ended with the triumph of the Christian Zagwe dynasty in Ethiopia. On a nearby front, the battles of Christians and Muslims along the Nile gave way to large-scale Arab migration upriver into the Sudan. Before and after this long struggle,
recurring flows of enslaved Africans and Eurasians were brought to the borderland from both north and south.
For sub-Saharan Africa as a whole during this era, connections expanded on the East coast and a bit on the North: thus, bananas, water yams, and maybe xylophones arrived on Africa's east coast from Southeast Asia and spread throughout the continent. In trade, Africa exported minerals and labor in this era. Horses imported across the Sahara enabled the rise of military states such as Kanem, Mali, and Songhai. It is of interest that Mali rose at the same time as the Mongol state, in the early thirteenth century: thus, in a moment of globalization, cavalry empires stretched most of the way from the Atlantic to the Pacific in the mid-thirteenth century. In the mid-fourteenth century, it is conceivable that much of Africa was affected by the plague pandemic. Archaeologists now provide preliminary reports of sharp declines in African construction activity at about the mid-fourteenth century, which open the possibility that the great epidemic of bubonic plague reached West Africa (Ife and southern Ghana), the East African highlands (Bigo), and perhaps even Zimbabwe (Chouin and Decorse 2010). Whether the spread of bacteria throughout the hemisphere counts as globalization, it was certainly a major episode in world history. The fifteenth- and sixteenth-century rise of African states (Congo, Luba, Jolof) might therefore be consistent with a post-epidemic rebound in population.
African and Eurasian comparisons and interactions, 1500-1850 As maritime commerce brought the shores of western Africa into contact with Eurasian societies, Africa and Eurasia became at once more similar and more distinctive. From the late seventeenth century, Atlantic commerce became focused especially on the export of captive laborers, as the European-controlled slave markets of the Americas expanded well beyond the size of their predecessors in the Afro-Eurasian borderland. The population of western Africa and eventually of the whole continent stagnated and even declined as a result of slave trade. Still, Africa largely avoided the institution of empire. The Ottomans controlled the northern fringe of Africa, while Portuguese, Dutch, English and French empires controlled small coastal enclaves. Of large African states, none reached imperial scale between the fall of Songhai in 1591 and the rise of the Sokoto Caliphate in 1804.
The Afro-Eurasian borderland remained mostly under Ottoman imperial control from 1500 to 1800, then gradually fell under Western European control. A final flourishing of Mediterranean and Arabian slavery took place in the eighteenth and nineteenth century. Eurasia in these centuries seemed focused on a great struggle between East and West, waged in terms of commerce, culture, and imperial domination. Africa has been virtually left out of this narrative, and it remains a challenge to identify the place of Africa in the early modern transformation of the Eastern Hemisphere. For the Americas, the relationship with Africa has been more fully clarified. On one hand it included a great exchange of biota and material culture between Africa and the Americas, including diseases, maize, manioc, peanuts, and fruits. On the other hand, both Europe and Africa had a great demographic and cultural input to the Americas. The ancestry of the current population of the Americas can be roughly estimated at 15 per cent Amerindian, 20 per cent African, and 65 per cent European, which provides one measure of the influence of Africa in the world beyond the continental limits.
Africa in the world since 1850
Africa in the nineteenth century experienced a dramatic expansion of enslavement and slave-based economies, just as slavery was abolished in the Americas. This distinctive socio-economic and political transformation needs much more study both in local context and as participation in the world system. Meanwhile, empire expanded rapidly into Africa by 1850, and at last seized full control of the continent at the end of the century. As a result, Africa underwent an extreme succession of political transformations: the rise of slave-based local systems, the imposition of colonial rule, and the transition to national independence though still under neocolonial hegemony. Colonial regimes imposed European languages of government as well as currency and trade arrangements that persistently drained African resources: both of these have persisted. The export of labor halted for most of this time, and Africa exported raw materials, agricultural and mineral, while importing manufactured goods. Colonial rule, in focusing each African territory on its European metropole, cut African lands off from each other, from the Afro-Eurasian borderland, and from the African diaspora in the Americas. Racial discrimination, already developed through the long history of enslavement, expanded to a disastrous peak during World War II. Remarkably, African cultural responses were especially robust, and fueled nationalist movements that brought a dramatic wave of independence in the 1960s and 1970s, and a movement toward continental political unity that was frustrated especially by external opposition.
The Afro-Eurasian borderland fell under colonial rule of Western Europe over a longer period of time but almost as firmly as for sub-Saharan Africa. The path to national independence there too was gradual. Among the distinctive developments of the region were the importance of petroleum resources and the rise of Arab nationalism. In Eurasia, World War I, fought mostly in the west, and World War II, fought at both ends of the continent, brought social revolution and the progressive collapse of empires. The postwar era provided an opening for renunciation of empire and race as organizing principles of society. In this era, popular culture of Africa and among African-descended people of the diaspora, emphasizing a bottom-up vision of social change, spread widely to help create a new and more democratic vision of social interaction.
Conclusion: Spatial, Ethnographic, and Temporal Lines of Globalization
I return to the questions posed at the start of this essay: what type of social change qualifies for the label 'globalization'? How large a geographic space must be encompassed within globalization? How long or short must an episode of globalization be? Could there be an episode of globalization within Africa and a separate episode of globalization within Eurasia? Could the shift in dominant economic organization from foraging to production, over the course of some ten thousand years, be seen as an episode of globalization? These questions of the spatial and temporal scale of globalization are at once simple and subtle. That is, the initial vision of globalization was that the society of the late twentieth century had encountered itself, for the first time, as a closed system - interaction with one another was suddenly inescapable. Yet if one allows for longer time frames, human society in earlier times can be treated as a closed system with interactions throughout it - and, with a stretch, one can even argue that there was consciousness of the whole human system.
More complicated than questions of space and time in globalization are the questions of how processes of social change are initiated and propagated. The narrative
above has encountered at least five categories of social change. First of these is exogenous change - that is, a major climatic, geologic, or disease change provokes initial social changes, and these changes are then propagated by other mechanisms. Second is the case of parallel changes - in this case, human agents create innovations out of their widely shared heritage, and the innovations provoke parallel changes in many parts of the world. Third is the case of unique, localized innovations - changes made only once or twice that spread thereafter too much of the world. Fourth is the case of changes brought by the functioning of networks - in this case widespread networks of social, cultural, economic, or political interactions bring transformations spreading both similarities and differences across the network. Fifth is the case of emergent properties -system-wide change that arises almost everywhere at once through unconscious interaction within the system. If this list of five provides an elementary set of types of social change, the question again arises as to which of these types of change can be considered to be globalization. Of the five, emergent properties strike me as the most obvious candidate for recognition as globalization. Diffusion of localized innovations seems to me to be the weakest candidate for recognition as globalization.
More learning can come from the successes and failures in the practical effort of fitting historical episodes into these analytical categories. For exogenous change, two important examples are the Younger Dryas, the thousand-year cold snap widely credited with launching planting agriculture, and the pandemics of Justinian's Plague and the Black Death. In each case, a shift in the natural world caused immense change in human society over a wide area, and set off a sequence of social changes. For parallel changes, we have numerous instances in which inherited knowledge and inclinations led to parallel inventions. Continuing experimentation with fire led repeatedly to ceramics and to metallurgy; continued experimentation with social relations led repeatedly to institutions of chiefdom. Other important and localized innovations occurred only once or twice. The domestication of horses and their deployment in warfare, while a slow process, spread transformation step by step throughout the world, yet had limited influence in Africa. The invention of writing systems took place numerous times, but the successful development of the social system of literacy took place only in Mesopotamia and China, and spread from there. As for changes through the functioning of networks, one may say that the early modern network of enslavement led by the nineteenth century to a globalization of forced labor throughout much of the world (Manning 1996). Finally, for emergent properties, I propose two examples. In early times and rather gradually came the shift in human logic and practice from foraging to production, during the Glacial Maximum and the early Holocene.4 In recent times and rather rapidly, national identity, the national form of government, and international relations emerged from underlying elements to transform society everywhere.
The focus on Africa in this essay is first of all for its own sake: to offer a statement of the importance of correcting the common neglect of Africa in analysis of current and historical affairs, with an attempt to provide some handy facts that will serve as reminders for the inclusion of Africa. More than that, the effort of proposing the corrective through comparison of Africa and Eurasia provides both questions and arguments of interest. It draws attention to the value of treating the African continent as an autonomous system, a large and populous region whose steady interactions over a long time have generated distinctive social organization. The approach also draws attention to the long borderland between Africa and Eurasia, whose particular prominence in world history must come
in part from its own local characteristics, but also from the repeated interactions with Africa on one side and Eurasia on the other. Thirdly, the approach draws attention to the value in considering the whole of the eastern hemisphere - Africa and Eurasia - as a single social system. Finally, and particularly because of its long time frame, the comparison of Africa and Eurasia encourages the comparison of many historical episodes over long periods of time, with all their similarities and differences. As a result, the focus on Africa and the comparison with Eurasia provides ample information for the continuing analysis of globalization in history.
NOTES
1 An expanded version of this approach could include Iberia and the Mediterranean islands: indeed, this is what Fig. 4 shows.
2 In tropical Asia the incoming Homo sapiens migrants may have encountered pre-existing communities descended from Homo erectus.
3 Before the development of iron technology, Eurasia had a well developed bronze age, relying on smelting of copper and tin, from roughly 5000 to 2500 years ago. As a parallel, examples of early copper metallurgy are gradually becoming apparent for Africa.
4 This transition was initially described by archaeologists in terms of Neolithic tools, but is here described in terms of human motivation.
REFERENCES
Bayly, C. A. 2004. The Birth of the Modern World, 1780-1914: Global Connections and
Comparisons. Malden, MA: Blackwell. Brooks, G. 1993. Landlords and Strangers: Ecology, Society, and Trade in Western Africa, 1000-1630. Boulder: Westview Press.
Chase-Dunn, C. 2006. Globalization: A World-Systems Perspective. In Chase-Dunn, C., and Babones, S. (eds.), Global Social Change: Comparative and Historical Perspectives (pp. 79-105). Baltimore: Johns Hopkins University Press. Chase-Dunn, C., and Hall, T. D. 2012. Global Scale Analysis in Human History. In Northrop, D. (ed.), A Companion to World History (pp. 185-200). Oxford: Wiley-Blackwell.
Chouin, G. L., and Decorse, C. R. 2010. Prelude to the Atlantic Trade: New Perspectives on Southern Ghana's Pre-Atlantic History (800-1500). Journal of African History 51: 123-145.
Gills, B. K., and Thompson, W. R. (eds.) 2006. Globalization and Global History. London: Routledge.
Hall, T. D. 2009. Puzzles in the Comparative Study of Frontiers: Problems, Some Solutions, and Methodological Implications. Journal of World-Systems Research 15(1): 25-47.
Hopkins, A. G. (ed.) 2002. Globalization and World History. New York: Norton. Livestrong 2013. What Is Average Caloric Intake of People? By Dray S. URL: http://www.livestrong.com/article/500181-what-is-average-caloric-intake-of-people/. Accessed 12 Jan. 2013). Maddison, A. 2001. World Economy: A Millennial Perspective. Paris: Development Centre of the Organisation for Economic Co-operation and Development.
Manning, P. 1996. Slave Trades, 1500-1800: Globalization of Forced Labour. Aldershot, UK: Variorum.
Manning, P. 2009. The African Diaspora: A History through Culture. New York: Columbia University Press.
Manning, P., and Nickleach, S. n.d. African Population, 1650-1950: The Eras of Enslavement and Colonial Rule. Forthcoming.
Manning, P., and Trimmer, T. 2012. Migration in World History. 2nd ed. London: Routledge.
McIntosh, S. K. 1995. Excavations at Jenne-Jeno, Hambarketolo, and Kaniana (Inland Niger Delta, Mali), the 1981 Season. Berkeley, CA: University of California Press.
Mongabay 2013. World Statistics (Sorted by Area). URL: http://mongabay.com/igapo/world_ statistics_by_area.htm. Accessed 8 Jan. 2013.
United Nations 2011. Demographic Yearbook. URL: http://unstats.un.org/unsd/demog raphic/products/ dyb/dyb2011.htm. Accessed 2 Jan. 2013.
United Nations 2012. Department of Economic and Social Affairs, Population Division. World Population Prospects: The 2012 Revision. URL: http://esa.un.org/unpd/wpp/ unpp/panel_population.htm. Accessed January 2, 2013.
Yang, B. 2011. The Rise and Fall of Cowrie Shells: The Asian Story. Journal of World History 22(1): 1-25.