Uneven Political Development:
Largest Empires in Ten world Regions and the Central International System since the Late Bronze Age*
Christopher Chase-Dunn, Hiroko Inoue, Alexis Alvarez,
Rebecca Alvarez, E. N. Anderson and Teresa Neal
Institute for Research on World-Systems
University of California, Riverside
Galactic or mandala polities in Southeast Asia
To be presented at the annual conference of the California Sociological Association,
Holiday Inn -- Capitol Plaza (near Old Town) Sacramento, November 13 and 14, 2015
An earlier version was presented at the Fourth European Congress on World and Global History, September 6, 2014, École Normale Supérieure, Paris
Draft v. 11-16-15, 11102 words
*We are indebted to those prodigious coders who made quantitative comparative studies of settlements and polities possible: Tertius Chandler, Rein Taagepera and George Modelski.
This is IROWS Working Paper #85 available at http://irows.ucr.edu/papers/irows85/irows85.htm
Data appendix for this paper is at http://irows.ucr.edu/cd/appendices/worregs/worregsapp.htm
The study of the long-run growth of settlements and polities is an important basis of our understanding of comparative sociology and human sociocultural evolution. The processes by which a world inhabited by small nomadic hunter-gatherer bands of humans became the single global political economy of today involved the establishment and growth of settlements, the expansion of interaction networks and the growing size of polities. These processes of long-term growth and expansion were uneven in time and space. There were cycles of growth and decline. And some of those regions that originally developed larger cities and polities were, in later epochs, no longer the leading regions.
Our theoretical approach is the institutional materialist comparative evolutionary world-systems perspective. World-systems are defined as being composed of those human settlements and polities  within a region that are importantly interacting with one another. This approach focuses on the ways that humans have organized social production and distribution, and how economic, political, and religious institutions have evolved in systems of interacting polities (world-systems) since the Paleolithic Age. We employ an underlying model in which population pressures and interpolity competition and conflict have always been, and still remain, important causes of social change, while the systemic logics of social reproduction and growth have gone through qualitative transformations (Chase-Dunn and Lerro 2014: Chapter 2). Our larger research project studies the development of settlements and polities by comparing regional world-systems and studying them over long periods of time.
Our approach to the spatial bounding of the unit of analysis is very different from those who try to comprehend a single global system that has existed for thousands of years. Gerhard Lenski (2005); Andre Gunder Frank and Barry Gills (1994) and George Modelski (2002; and Modelski, Devezas and Thompson 2008) and Sing Chew (2001; 2007) all analyze the entire globe as a single system over the past several thousand years. We contend that this approach misses very important differences in the nature and timing of the development of complexity and hierarchy in different world regions. Combining apples and oranges into a single global bowl of fruit is a major mistake that makes it more difficult to both describe and explain social change. Our comparison of different world regions and interaction networks of polities makes it possible to discover both the similarities and the differences. Global comparisons among these regional systems are certainly appropriate, but the claim that there has always been a single global world-system is profoundly misleading. 
Our earlier studies have used data on city sizes and the territorial sizes of empires to examine and compare different regional interaction systems (e.g. Chase-Dunn, Manning and Hall 2000; Chase-Dunn and Manning 2002; Inoue et al 2012; Inoue et al 2015). This article is a re-examination of the empire size data that uses better estimates and that will enable us to address claims about the relative importance of China and Europe that have been advanced by Andre Gunder Frank (1998) and more recently by Ian Morris (2010; 2012) and to reflect on the similarities and differences of the trajectories of development in the ten world regions we are studying.
The question we will try to answer in this article is: what can patterns of polity growth tell us about the trajectories of development of the different world regions and the expanding Central System? This paper is the second part of a study that also uses the sizes of largest cities in world regions to examine the nature of uneven development (Chase-Dunn, Inoue, A. Alvarez, R. Alvarez, Anderson and Neal 2015). But this paper looks only at the sizes of the largest polities in each world region.
The issue of systemness and the spatial boundaries of whole human systems remains contentious in social science. The description of Earth-wide “global” history and processes is certainly a valid exercise, but the question of bounding whole systems is more complicated. It depends on what is meant by systemness. The idea of a whole system requires being explicit about what is within the system and what is designated as exogenous. Some explicit world-systems theoretical approaches claim that the whole of humanity has constituted a single world-system since the emergence of modern humans. This position has been explicitly taken by Gerhard Lenski (2005). Andre Gunder Frank and Barry Gills (1994) contended that what they call “the world system” emerged when states and cities arose in Mesopotamia 5000 years ago. Frank and Gills (1993:16, 84-85) designated a number of turning points of gradual inclusion of world regions into the world system. Five thousand years ago it was constituted only as Egypt and Mesopotamia, but China and the rest of Eurasia became part of the system around 500 BC, and the incorporation of Americas occurred after 1492. Their position was adopted by Sing Chew 2001; 2007, but see 2014).
Immanuel Wallerstein (2011) contended that the modern world-system was not yet global when it emerged in Europe and the Americas in the long 16th century CE. Chase-Dunn and Hall (1993; 1997) defined world-systems as human interaction networks in which the interactions were two-way and regular. They adopted a place-centric approach to spatially bounding world-systems because of the observation that all human groups interact with their neighbors and so if you count all indirect connections there has been a single linked network since the humans populated the continents. The ideas of “fall-off” of effects of interaction and place-centricity were adopted from archaeology.
The study of world regions that we have undertaken here is not meant to confound the spatial bounding of whole human interaction systems by means of interaction networks. Rather it is intended to shed light on the literature that has emerged from the critique of Eurocentrism and the rise of other centrisms. We acknowledge that Eurocentrism has had huge detrimental effects on the efforts of social scientists to describe and explain human sociocultural evolution. And we agree that looking at reality from different perspectives is a valuable exercise that can be enlightening and make big contributions to the effort to explain the human past and present. We contend that the methodological approach developed by Chase-Dunn and Hall for spatially bounding world-systems is capable of providing a non-centric (or cosmocentric) method for comparing small, medium-sized and large whole human systems. This said, we admit that important work still needs to be done to accurately specify the timing and location of changes in the spatial boundaries of world-systems (see Chase-Dunn, Wilkinson, Anderson, Inoue and Denemark 2015).
Results of Our Earlier Studies of Scale Changes of Polities and Settlements
Our studies have used data on city sizes and the territorial sizes of empires to examine and compare different regional interaction systems (e.g. Chase-Dunn, Manning and Hall 2000; Chase-Dunn and Manning 2002; Inoue et al 2012; Inoue et al 2015). We have identified those instances in world history for which quantitative indicators are available in which the scale of polities and settlements have greatly increased. These are termed upsweeps (Inoue et al 2012; Inoue et al 2015). We also identify downsweeps and system-wide collapses in which the largest polities or settlements declined below the level of the previous low point and stayed down for more than one typical cycle. Using this method we found that, while the decline of individual cities and empires was part of the normal cycle of rise and fall, there were very few system-wide collapses in which a downsweep was not followed very soon by another rise.
We also found a greater rate of urban cycles in the Western (Central) system than in the East Asian system, which supports the usual notion that the Western city system was less stable than the Eastern city system. And our finding that the Central system experienced two urban collapses, while the Eastern system experienced downsweeps but not collapses, supports the idea of greater stability in the East. We found that nine of the eighteen urban upsweeps we identified were produced by semiperipheral development and eight directly followed, and were caused by, upsweeps in the territorial sizes of polities.
We also examined twenty-four upward sweeps of the largest polities in four world regions and in the expanding Central interpolity system since the Bronze Age to determine whether or not the upsweeps were (or were not) semiperipheral marcher states. (Inoue, Álvarez, Anderson, Lawrence, Neal, Khutkyy, Nagy and Chase-Dunn 2013). We found that over half of the twenty-two identified empire upsweeps were likely to have been produced by marcher states from the semiperiphery (10) or from the periphery (3). This means that the hypothesis of semiperipheral development does not explain everything about the events in which polity sizes significantly increased in geographical scale, but also that semiperipheral development must not be ignored in any explanation of the long-term trend in the rise of polity sizes.
Relative Regional Complexity
Andre Gunder Frank’s (1998) provocative study of the global economy from 1400 to 1800 CE contended that China had long been the center of an already global system. Frank also argued that the rise of European power was a sudden and conjunctural development caused by the emergence in 18th century China of a “high level equilibrium trap” and the success of Europeans in using bullion extracted from the Americas to buy their way into Chinese technological, financial and productive success. Frank contended that European hegemony was fragile from the start and will be short-lived with a predicted new rise of Chinese global predominance in the near future. He also argued that scholarly ignorance of the importance of China invalidates all the social science theories that have mistakenly characterized the rise of the West and the differences between the East and the West. In Frank’s view there never was a transition from feudalism to capitalism that distinguished Europe from other regions of the world. He argued that the basic dynamics of development have been similar in the single global system for 5000 years (Frank and Gills 1994).
A related effort to compare world regions as a window on relative sociocultural evolution is contained in two recent books by Ian Morris (2010; 2012). Morris’s big idea is that complex human systems, like other complex systems, need to capture free energy in order to support greater scale and complexity, and that the ability to capture free energy is the main variable that accounts for the growth of cities and empires in human history. Morris traces the increasing size of human settlements since the origins of sedentism in the Levant about 12,000 years ago. And he uses estimates of the sizes of the largest settlements in world regions as a main indicator of system complexity. Using this method he notes that there was parallel evolution of sociocultural complexity in Western Asia and Northern Africa, South Asia, East Asia, the Andes and Mesoamerica, and that the leading edge of the development of complexity diffused also from its points of origin. And sometimes the original centers of complexity lost pride of place because new centers emerged out on the edge. The Bronze Age Mesopotamian heartland of cities now has none of the world’s largest cities. Development was spatially uneven in some regions, with the center moving to new areas.
In the introductory chapter of The Measure of Civilization Morris provides a useful overview of earlier efforts to measure social development, and he also provides a helpful and insightful discussion of the social science literature on sociocultural evolution since Herbert Spencer. Morris’s research is unusual for an historian because he carefully defines his concepts, specifies his assumptions and operationalizes his measures, and then uses the best quantitative estimates of settlement sizes as the main basis of the story he is telling. His estimates of the sizes of the largest cities utilize, and improve upon, earlier compendia of city sizes.
The main focus of Morris’s Why the West Rules is the comparison of what happened in Western Asia, the Mediterranean and Europe with what happened in East Asia. Morris is careful to trace the histories of the diffusion of complexity in these areas. Morris makes contemporaneous comparisons between the East Asian and Western regions in which he notes the existence of a see-saw pattern back and forth regarding which region was ahead or behind in the development of sociocultural complexity. The West (Western Asia) had an original head-start, but the East caught up and passed, and then the West (Europe and North America) passed the East again.
While The Measure of Civilization is about the quantitative basis of Morris’s analysis, Why the West Rules adds a lot of detail beyond the basic focus on energy capture. But the energy capture idea misses some of the patterns that are of interest to those who want to study whole world-systems over long historical time. The story tends to be rather core-centric with little attention paid to the transformative roles played by peripheral and semiperipheral marcher states and city-states in the construction of large empires and the expansion of trade networks. Morris does not discuss the transformation of systemic logics of development over the long period he studied, or how differences in the development of capitalism may have been an important contributor to the rise of Europe. But the foregrounding of energy and cities is a valuable strategy for comprehending both the patterns of history and for considering the present and the future of human sociocultural development.
Immanuel Wallerstein’s (2011 ) analysis of East-West similarities and differences that account for the rise of predominant capitalism in Europe and the continued predominance of the tributary logic in East Asia is presented in Chapter One of Volume 1 of The Modern World-System. Summing up his detailed discussion of the main factors that account for the East/West divergence, Wallerstein says:
The essential difference between China and Europe reflects once again the conjuncture of a secular trend with a more immediate economic cycle. The long-term secular trend goes back to the ancient empires of Rome and China, the ways in which and the degree to which they disintegrated. While the Roman framework remained a thin memory whose medieval reality was mediated largely by a common church, the Chinese managed to retain an imperial political structure, albeit a weakened one. This was the difference between a feudal system and a world-empire based on a prebendal bureaucracy. China could maintain a more advanced economy in many ways than Europe as a result of this. And quite possibly the degree of exploitation of the peasantry over a thousand years was less. To this given, we must add the more recent agronomic thrusts of each, of Europe toward cattle and wheat, and of China toward rice. The latter requiring less space but more men, the secular pinch hit the two systems in different ways. Europe needed to expand geographically more than China did. And to the extent that some groups in China might have found expansion rewarding, they were restrained by the fact that crucial decisions were centralized in an imperial framework that had to concern itself first and foremost with short-run maintenance of the political equilibrium of its world-system. So China, if anything seemingly better placed prima facie to move forward to capitalism in terms of already having an extensive state bureaucracy, being further advanced in terms of the monetization of the economy and possibly of technology as well, was nonetheless less well placed after all. It was burdened by an imperial political structure (p. 63).
We now know much more about China because of the careful comparative work of the “California School” of world historians (e.g., Bin Wong 1997; Kenneth Pomeranz 2001) and Giovanni Arrighi’s Adam Smith in Beijing (2007) as well as the important collection of essays in Arrighi, Hamashita, and Selden (2003). But Wallerstein’s analysis of the main elements explaining the East/West divergence since the sixteenth century is still the best because of its fruitful combination of millennial and conjunctural time scales.
Frank’s model of development in Reorient focuses mainly on state expansion and financial accumulation. His study of global flows of specie, especially silver, was an important contribution to our understanding of what happened between 1400 and 1800 CE (see also Flynn 1996). Frank also uses demographic weight, and especially population growth and growth of the size of cities, as an indicator of relative developmental success.
It is our intention to systematically examine the growth of the largest settlements and polities in order to shed more light on Frank’s and Morris’s claims about the relative development of East and West. Our study will begin in 1500 BCE when we first have reliable absolute years for the population sizes of cities and the territorial sizes of states and empires in different world regions.
Chronologies for Comparative Analysis
For purposes of comparing the timing of changes in city and polity sizes across different world regions it is important to have accurate absolute chronologies for the regions being compared. Unfortunately there is still considerable disagreement about the absolute dating for Mesopotamia before 1500 BCE. Mario Liverani (2014: 9-16) explains why estimates of absolute dates are so uncertain. Relative dates of events needed for estimating polity sizes are based on “king lists.” Thus an event, such as a conquest, is said to have occurred in the third year of the reign of King X. Considerable effort has been made to figure out the correspondences between different king lists in Mesopotamia and their correspondence with Egyptian king lists. These are then converted in to calendar years by ascertaining their relationships with astronomical events such as eclipses. Unfortunately there is a period after the fall of the Babylonian empire in which king lists are missing for Mesopotamia, and there is disagreement about the timing of astronomical events. Thus the length in years of the occluded period is in dispute, and this results in so-called, short, medium and long chronologies for the period before the Late Bronze Age, with an error of as much as 100 years. Our efforts to estimate the sizes of polities are dependent on absolute dating because we want to compare across world regions. So it matters to us whether Ur was sacked in 2004 BCE, and thus is eliminated from the list of large cities and large polities in 2000 BCE, or in some other year 50 years earlier or later. Liverani (2014: 15) is satisfied to use the middle chronology for Mesopotamia and the surrounding regions, but he is not trying to compare the timing of changes in the Ancient Southwest Asia with other world regions. So we begin in 1500 BCE.
Another temporal issue that we should mention is the effort we have made to code the sizes of polities as snap-shots taken every 100 years. George Modelski (2003) had already organized the city population estimates into 100 year intervals, but Rein Taagepera’s (1978a;1978b; 1979; 1997) estimates of polity sizes were organized according to the year of the events that caused changes in the sizes of polities, mainly conquests and rebellions. In order to be able to compare city and polity sizes we converted Taagepera’s estimates to the same time points as we are using for cities by means of interpolation. We also improved upon Taagepera’s estimates by using more recent Atlases and web sources such as Geacron and Wikipedia that have information about the history of polities. But using 100-year snap-shots could miss some important developments that are relevant to the study of scale changes in polity and city sizes. So, for example, in order not to miss the huge but short-lived Mongol Empire we have added 1250 CE as a time point.
Units of analysis: world regions and interaction networks
The comparative evolutionary world-systems perspective spatially bounds world-systems as networks of interacting polities (Chase-Dunn and Hall 1997: Chapter 3; Chase-Dunn and Jorgenson 2003). In most of our studies we use political/military interaction networks (PMNs) composed of fighting and allying polities as the unit of analysis. But in this paper we want to examine the different trajectories of world regions. PMNs have the disadvantage that they expanded and contracted over time as smaller regional networks merged or were engulfed by larger systems, eventuating in the single global system of today. Thus all the world regions eventually became incorporated into a single global network that we call the Central International System, following Wilkinson (1987). In order to compare the trajectories of different world regions, which is the main purpose of this article, we will hold the spatial boundaries of the ten specified different regions constant over time. This allows us to trace the timing and trajectories of changes in the spatial scale of settlements and polities without worry that the changes we find are due to alterations in the spatial boundaries of the regions we are studying. We will also want to compare our constant region findings with studies of expanding political-military networks, especially the Central PMN.
Thus the main unit of analysis in this study is the world region, and regions are held constant over the whole period. The ten regions we will study are:
1. Europe, including the Mediterranean and Aegean islands, that part of the Eurasian continent to the west of the Caucasus Mountains, but not Asia Minor (now most of Turkey).
2. Southwest Asia- Asia Minor (now Turkey), the Arabian Peninsula, Mesopotamia, Syria, Persia, the Levant, and Bactria (Afghanistan), but not north of Afghanistan.
3. Africa, including Madagascar.
4. The South Asian subcontinent, including the Indus river valley and Sri Lanka.
5. East Asia, including China, Korea, Japan and Manchuria.
6. Central Asia and Siberia: We define Central Asia broadly as: the territory that lies between the eastern edge of the Caspian Sea (longitude E53) and the old Jade Gate near the city of Dun Huang near longitude E95, and that is north of latitude N37, (which is the northern edge of the Iranian Plateau, the northern part of Afghanistan and the mountains along the southern edge of the Tarim Basin). The northern boundary is the northern edge of the steppes as they transition into forest and tundra. So the Central Asia region we are studying includes deserts, mountains and grasslands (steppes) (Hall et al 2009).
7. Southeast Asia, including Indonesia, Malaysia, the Philippines, Cambodia, Burma, Vietnam and Thailand.
8. Oceania, the islands of the Pacific including Australia, New Zealand and Borneo (Papua and Papua New Guinea).
9. North and Central America
10. South America, including Panama and the Caribbean Islands
For some purposes we will also use the expanding Central PMN as a unit of comparison.
The ten specified world regions are defined for purposes of examining the claims made by Frank and Morris about relative development of cities and empires (see Figure 1).  These specified world regions are somewhat arbitrarily bounded but we have developed this spatial set of categories based on our knowledge of where large cities first emerged, and with attention to the issue of large empires.
Figure 1: The ten world regions we are using for comparisons
Measures of relative complexity based on the territorial sizes of empires
Determining relative sizes requires real metric (interval-level) estimates, not just periodizations of growth and decline. What we want to know is the size of the area over which a central power exercises a degree of control that allows for the appropriation of important resources (taxes and tribute). The ability to extract resources falls off with distance from the center in all polities, and controlling larger and larger territories requires the invention of new transportation, communications and organizational technologies [what Michael Mann (1986) has called “techniques of power”]. Military technologies and bureaucracies are important institutional inventions that make possible the extraction of resources over great distances, but so are new ideologies and new technologies of communication (Innis 1950). Political boundaries between states were not usually as formalized before the modern era, and so these boundaries were often fuzzy regions of declining ability to extract resources. The galactic or mandala model of state structure developed by Stanley Tambiah (1977) to understand political structures in Southeast Asia is broadly applicable. Thus the territorial size estimates that have been compiled for Bronze and Iron Age polities contain a rather large error component and these estimates, like the estimates of the population sizes of cities, need to be continuously evaluated with consideration to recently developed historical knowledge about the polities and regions.
Not all maps in political atlases show the boundaries of territorial control. They may represent linguistic or religious groups or other distinctions that have little or nothing to do with state power. And maps may not have good time resolution. Our estimates of the territorial sizes of polities are mainly derived from the published articles of Rein Taagepera (1978a, 1978b, 1979, 1997). Following Taagepera, we use square megameters to indicate the territorial sizes of polities. A square megameter is a territory that is 1000 by 1000 kilometers in size.
Of course territorial size is only a rough indicator of the power of a polity because areas are not equally significant with regard to their ability to supply resources. A desert empire may be large but weak. But this rough indicator is quantitatively measureable in different world regions over long periods of time, so it is valuable for comparative historical research.
Estimating the territorial sizes of states and empires is based on the use of published historical atlases and histories. It is very difficult to estimate the sizes and political boundaries of polities with archaeological evidence alone. So documentary evidence is the basis of these estimates. For the ancient and classical worlds these are based primarily on knowledge about who conquered which city, and whether or not and for how long tribute was paid to the conquering polity. Knowledge of rebellions is also used to gage instances in which states get smaller. Only asymmetrical (unequal) exchange signifies a tributary imperial relationship. Otherwise it is just trade and does not signify an extractive relationship and a boundary of political control. Sometimes it is difficult to tell whether or not tribute is asymmetrical or symmetrical exchange. Chinese dynasties often required formal suzerainty and tribute from other states but also sent elaborate gifts to their alleged vassals. In some cases (as with Central Asian steppe confederacies) the balance seemed to have gone away from China rather than toward it.
Polities not only get larger, but their structures evolve over the period of our study. Early states expanded into territorial empires, and then large non-contiguous colonial empires emerged, and then these were replaced by contiguous modern nation-states. Most of the large ancient and classical empires involved the conquest of territory that that was contiguous with the home territory. But once naval power was taken up by tributary states an empire could conquer and dominate a client state that was far from its home territory, such as Rome’s control of areas on the south shore of the Mediterranean Sea. If these distant non-contiguous tribute-payers were small in number and/or size, not including them in the estimates of the territorial sizes of empires would not constitute a large error. But, as capitalism moved from the semiperiphery to the core, capitalist nation-states increasingly adopted the thallassocratic form of empire that had been pioneered by semiperipheral capitalist city-states—control over distant overseas colonies. The modern colonial empires (British, French, etc.) require estimating the territorial sizes of colonies that are spread across the seas. Waves of decolonization have eventuated in the contemporary international system of polities in which the largest are contiguous modern nation-states such as Russia, the United States, Brazil, etc.. The increasing institutionalization of the territorial boundaries of states makes it much easier to determine the territorial sizes of polities than it was in the ancient and classical worlds in which polity boundaries were often very fuzzy.
Comparing polity sizes across world regions and PMNs
The results of our comparisons of relative sizes of polities have important implications for the huge literature that compares the trajectories of state formation and economic development in East Asia with that of the West. Most of the earlier literature compares China with Europe. Our use of world regions allows us to compare East Asia with Europe, but also to track the political military network (PMN) that came out of Mesopotamia and Egypt and expanded west to include the Mediterranean, and eventually the Americas and east to include South Asia. This is a comparison of the East Asian PMN with the Central PMN. States and empires sometimes cross the boundaries between our designated world regions. When this happens we assign the territorial size of the polity to the region that contains its capitol.
Walter Scheidel’s (2009) insightful consideration of the similar and different trajectories of China and the Mediterranean contends that there were two great divergences. The one that occurred in the 18th and 19th centuries has received a lot of attention from Ken Pomeranz (2000), who named it “the great divergence”, but also from Bin Wong (1997) and Andre Gunder Frank (1998). Scheidel (2009) notes that there was an earlier great divergence between China and the West. Both the Roman and the Han empires managed to bring huge territories under a single authority, but after they declined different things happened in the West and the East. In the East the decline of the Han was followed, after an interval, by the rise of the Tang empire, which was nearly as large as the Han had been. In the West, after the fall of Rome another empire of a similar huge size, uniting the entire Mediterranean littoral, never rose again. This was the first great divergence. Scheidel (2009: 12-13) also compares the percentage of time that the core of each region has been politically united. He cites Victoria Hui (2008:59) regarding the percentage of time between 214 BCE and 2000BCE that the Chinese core, defined as the region controlled by the Qin dynasty at its height in 214 BCE, has been united (42%). Hui is making the point that China has been less united than most observers believe, but Scheidel (2008:13) reports that “the western ecumene that was under Roman rule at the death of Augustus in 14 CE” has been united for only 18% of the time, and not at all for the past 16 centuries. Empires did emerge in the West after the fall of Western Rome, but none of them were able to take over the entire core region that had been held by Rome. 
The first great divergence can be seen in Figure 5 below. Scheidel contends that geographical and climate differences do not explain the first divergence. He assumes that empires are easier to erect when there are fewer barriers to transportation and communication. He asserts that the core region of China in two river valleys is a more difficult region to integrate relative to the Mediterranean littoral because mountain ranges separate the valleys. Indeed central regulation and control may be less needed in a system in which the network structure was itself less centralized or linear. Greater transportation and communications costs (up to a point) give greater incentives for the non-center to go along with the center because the center provides access to many different locales.
The Mediterranean “Middle Sea” allowed many network nodes to connect directly with many other nodes. Centralized control was not needed in order to facilitate interaction. In China the Grand Canal project that linked the valley of the Huang He River with the river valleys of the south by water required a centralized authority to build and maintain it while the Middle Sea did not. Of course there were several other differences that may have contributed to the first great divergence. Phonetic alphabets had been adopted in the West, allowing local languages to each be written in their own way, but making cross-language communication more difficult. The ideographic characters used in China allowed different languages to use the same symbols, making it possible for speakers of very different languages to read the same documents. Scheidel also mentions the possibility that differences in the nature of the legitimation of authority may have facilitated centralization in China, but not the West. The Chinese state used legalism and Confucianism, while the West experienced competing (and conflicting) transcendent otherworldly religions.
Figure 2: Sizes of largest polities in Europe and in the Central PMN
We will be comparing East Asia with both Europe and the Central PMN below but the first question is to compare Europe and the Central PMN to one another. So Europe and the Central PMN overlap over most of the period we are studying, but the Central PMN is larger. When Morris and Scheidel compared East Asia (mainly China) with “the West” they were usually thinking about what we here call the Central PMN. But much of the literature on East/West comparisons is about Europe (the “little West”) and China. So here we do both. Figure 2 shows the differences that it makes when we look at the largest polities in the expanding Central PMN vs. in Europe as a constant world region. These two series are rather highly correlated (partial Pearson’s r = .78, see Table 2 below) but they diverge during certain periods. The big divergences are due to the rises of the Persian, Islamic and Mongol Empires, all of which had capitals outside of Europe but within the Central PMN. We included Central Asia in the Central PMN after 30 CE (see Footnote 11 above) because of the Kushan Empire, but Central Asian steppe confederacies such as the Xiongnu were obviously important players in the East Asian PMN since 212 BCE. The Eastern and Western PMNs overlapped to some extent in Central Asia. But, with the exception of the short-lived Mongol Empire, direct connections did not exist until the 19th century CE. The issue here is to what extent could indirect connections be strong enough to constitute systemness. This issue will be investigated in a workshop on the spatial bounding of world-systems (see Chase-Dunn, Wilkinson, Anderson, Inoue and Denemark 2015).
Figure 3: Sizes of largest polities in each of 10 world regions (square megameters): 1500 BCE- 2010CE
Figure 3 shows the sizes of the territories of the largest polities in each of our ten world regions from 1500 BCE until 2010 CE. There is the long-term trend toward larger polities in evidence in all the world regions, but also ample evidence of the patterns of rise and fall in each.
This graph is rather different from the one produced by studying city sizes in all the regions (Chase-Dunn, Inoue, A. Alvarez, R. Alvarez, Anderson and Neal 2015: Figure 3).
The scale change for cities was far larger than the scale change for polities over the last 3500 years. In 1500 BCE the largest city had only 75,000 people but by 2010 CE Tokyo had nearly 37 million people – a ratio increase of more than 492. When we use the built-up area of cities the same scale change ratio for Thebes and Tokyo is much greater (1696, see Table 1). But for polities the territorial size scale change goes from .65 square megameters for the Theban state to 17.1 square megameters for the Russian Federation in 2010 CE. This is a scale change ratio of only 26. The largest single formal empire ever was the British Empire in 1900 CE with 29 square megameters of territory, a ratio scale change of just 45 compared with Thebes in 1500 BCE. So cities have grown much more than polities have over the last three and one half millennia.
Largest City (Population)
Russian Federation 17.1
Scale change ratio
Table 1: Urban and Polity Territory Scale Changes, 1500 BCE to 2010 CE
The city populations took off exponentially in the 19th century but the polity sizes came down or leveled out because of collapse of the territorial and colonial empires. Of course, as we have mentioned above, formal political control over territory is not the only way that imperialism can be organized. The extensive literature on neo-colonialism, hegemony and new forms of globalized empire is germane here. But the overall trend toward larger formal states is evident in the period since 1500 CE. It is hard to compare world regions when we put them all in the same graph, but the strange trajectory of Central Asia stands out in Figure 3, with the Mongol Empire showing itself as having been the 2nd largest territorial empire in world history.
Figure 4: Percentage of each region held by its largest polity of the sum of the largest polities in all ten regions
This is what happens when we pit all the world regions against one another. The percentages in Figure 4 are based on the denominator obtained by adding all the territorial sizes in each of the regions together. We should note that our data set is still not complete (see count of missing cases in Appendix), but the main patterns displayed in Figure 4 will probably hold up when more estimates are added. This a very complex set of patterns and it is hard to see what is going on when we have all ten world regions. But some things jump out. The most obvious is the 500 BCE overwhelming predominance of the Persian Empire in a period in which the other regions had only small states. We should remind the reader that we place an empire in its region depending on where its capital is located. So the Persians conquered Egypt, but Southwest Asia gets the points. Another interesting feature of Figure 4 is what percentaging does to the relative standings of the Mongol and British Empires. From the point of view of relative size, the Mongols had a greater percentage than the British did, though neither come close to the relative predominance of the earlier Persian Empire. Persia was the proverbial 800 pound gorilla of the Central PMN.
Figure 5: Sizes of largest polities in Europe and East Asia (square megameters): 1500 BCE- 2010CE
Figure 5 has the same numbers as Figure 3 above but without including the other seven world regions. This figure shows the sizes of the largest states and empires in Europe and East Asia since 1500 BCE. Again both regions show the overall long-term trend toward greater polity sizes and also the sequences of shorter-term rises and falls. Of interest here are the two great divergences discussed above and the issue of synchrony vs. see-sawing. We also want to compare the East Asian trajectory with that of the Central PMN as well as with Europe. When we look at Europe’s trajectory vis a vis East Asia in Figure 5 we can see that the rise of the Han Empire in China began earlier than the rise of large Macedonian and Roman empires in Europe and the decline began earlier in East Asia than it did in Europe. This has implications for Scheidel’s notion of the first divergence because the waves of empire formation were not entirely synchronous. China did it first, followed not long after by Europe. The European peak then last rather longer that the Chinese peak did. This was what many have observed as the unusually long tenure of the Roman Empire. Then Europe went into a long slump while Tang China recovered. With regard to the second great divergence, the territorial size trajectories imply something different from Gunder Frank’s notion of stable Chinese centrality and late and unstable European predominance. The new rise of Europe begins earlier than Frank claims (in the 15th century, not in the 18th) and Qing China is also getting larger but ends up only half as large as the British Empire.
Figure 6: Sizes of largest polities in East Asia and the Central PMN (square megameters): 1500 BCE- 2010CE
Figure 6 compares the largest polities in East Asia with those in the expanding Central PMN. Recall that East Asia becomes part of the Central PMN in the middle of the 19th Century CE but we can still compare the part with the whole after that. Things look a bit different than when we compared with only the “little West.” The Persian Empire, with its capital in Southwest Asia rises and falls before the emergence of the Han. And the Islamic Empires are larger and synchronous with the Tang. And since we have included Central Asia in the Central PMN, the Mongol Empire appears just ahead of the very large Yuan Empire which was, of course, founded by the Mongols. After 1500 CE the story is the same as in Figure 6 because European powers, including the British Empire and Russia, were the largest territorial polities. So Figure 6 seems to display much more East/ “West” similarity than Figure 5 does.
The partial Pearson’s r correlation coefficients among East Asia, Europe and the Central PMN are shown in Table 2.
Region or PMN
.78 sig = .000
.57 sig =.000
.78 sig =.000
.51 sig =.001
East Asian Region and PMN
.57 sig = .000
.51 sig = .001
Table 2: Pearson’s r partial correlation coefficients (controlling for Year) for territorial sizes of the largest polities in East Asia, Europe and the Central PMN from 1500 BCE to 2010 CE (n= 39)
Table 2 contains the correlation coefficients produced by partial correlations in which year is held constant to control for the long-term upward trend in the territorial sizes of polities. Unsurprisingly given that Europe is an important part of the Central PMN, there is a .78 positive correlation across the 3500 year period studied. But somewhat more surprising are the positive and statistically significant partial correlations between Europe and East Asia and between the Central PMN and East Asia. Contrary to our examination of Figures 5 and 6 above, the partial correlation between the Central PMN and East Asia is somewhat smaller than the partial correlation between Europe and East Asia.
Urban and Polity Conclusions
Our study of the largest cities in world regions suggested problems with Andre Gunder Frank’s (1998) characterization of the relationship between Europe and China before and during the rise of European hegemony and the results of this study of largest polities find the same things. Frank’s contention that Europe was primarily a peripheral region relative to the core regions of the Afro-eurasian world-system is supported by the city and polity data, with some qualifications. Europe was for millennia a periphery of the large cities and powerful empires of ancient Southwest Asia and North Africa. The Greek and Roman cores were instances of semiperipheral marcher states that conquered important parts of the older Southwest Asian/North African core. After the decline of the Western Roman Empire, the core shifted back toward the East and Europe was once again importantly peripheral. We find partial support for Walter Schiedel’s idea of the first great divergence between East and West after the decline of the Western Roman Empire. Scheidel’s observation that the Mediterranean was never again united as it had been under Rome is correct, but the rise the Islamic Empires, part of the Central PMN was substantially synchronous with the rise of the Tang dynasty in China. We also find more synchrony than the see-sawing described by Morris, which would produce negative rather than positive correlation coefficients.
Our urban and polity synchrony findings support the idea proposed in Frank and Gills (1994) that there was an integrated Afro-eurasian world-system much earlier than most historians and civilizationists suppose. But we cannot yet be certain that interaction networks were the important causes of the synchrony and, if they were, we do not know which kind of interactions were most important.
Counter to Frank’s contention, however, the rise of European hegemony was not a sudden conjunctural event that was due solely to a developmental crisis in China. The city population data indicate that an important renewed core formation process had been emerging within Europe since at least the 14th century. This was partly a consequence of European extraction of resources from its own expanded periphery that is seen in the expansion of the European colonial empires. But it was also likely due to the unusually virulent form of capitalist accumulation within Europe, and the effects of this on the nature and actions of states. The development of European capitalism began among the city-states of Italy. It spread to the European interstate system, eventually resulting in the first capitalist nation-state (the Dutch Republic of the seventeenth century) as well as the rise of the hegemony of the United Kingdom of Great Britain in the nineteenth century. This process of regional core formation and its associated emphasis on capitalist commodity production further spread and institutionalized the logic of capitalist accumulation by defeating the efforts of territorial empires (Hapsburgs, Napoleonic France) to return the expanding European core to a more tributary mode of accumulation.
Acknowledging some of the uniquenesses of the emerging European hegemony does not require us to ignore the important continuities that also existed as well as the consequential ways in which European developments were linked with processes going on in the rest of the Afroeurasian world-system.
The more recent emergence of East Asian cities as again the very largest cities on Earth occurred in a context that was structurally and developmentally distinct from the militarily multi-core system that still existed in 1800 CE. Now there is only one global core because all the core states are directly interacting with one another. While the military multi-core system prior to the nineteenth century was undoubtedly systemically integrated to an important extent by trade and information flows, it was not as interdependent as the global world-system became in the nineteenth century.
A new East Asian hegemony is by no means a certainty, as both the United States and German-led Europe will be strong contenders in the coming period of multi-polar hegemonic rivalry (Bornschier and Chase-Dunn 1999; Chase-Dunn, Kwon, Lawrence and Inoue 2011). The transition from territorial empires to colonial empires and now to a global polity composed of formally sovereign nation states has not ended the long evolutionary trend toward larger and larger polities. This trend can continue to be seen in the trajectory of the increasing size of the capitalist states that have assumed the role of leadership and hegemony in the modern world-system, first the tiny Dutch Republic of the 17th century, then the British Empire and now the continental-sized United States. The forms of power have evolved, but uneven development and the processes of rise and fall continue.
Abu-Lughod, Janet Lippman 1989. Before European Hegemony The World System A.D. 1250-1350
New York: Oxford University Press.
Amin, Samir 1980. Class and Nation, Historically and in the Current Crisis. New York: Monthly
Anderson, E. N. and Christopher Chase-Dunn “The Rise and Fall of Great Powers” in
Christopher Chase-Dunn and E.N. Anderson (eds.) 2005.
The Historical Evolution of World-Systems. London: Palgrave.
Arrighi, Giovanni 1994. The Long Twentieth Century. London: Verso.
______________ 2008 Adam Smith in Beijing. London: Verso.
Arrighi, Giovanni, Takeshi Hamashita, and Mark Selden 2003 The Resurgence of East Asia :
500, 150 and 50 Year Perspectives. London: Routledge
Barfield, Thomas J. 1989 The Perilous Frontier: Nomadic Empires and China. Cambridge, MA.:
Beaujard, Philippe. 2005 “The Indian Ocean in Eurasian and African World-Systems Before
the Sixteenth Century” Journal of World History 16,4:411-465.
_______________ 2009 Les mondes de l’océan Indien Tome I: De la formation de l’État au
premier système-monde Afro-Eurasien (4e millénaire av. J.-C. – 6e siècle apr. J.-C.).
Paris: Armand Colin.
_______________2010. “From Three possible Iron-Age World-Systems to a Single Afro-
Eurasian World-System.” Journal of World History 21:1(March):1-43.
_______________ 2112 Les mondes de l’océan Indien Tome II: L’océan Indien, au coeur des
globalisations de l’ancien Monde du 7e au 15e siècle. Paris: Armand Colin
Beckwith, I. Christopher. 1991. "The Impact of the Horse and Silk Trade on the Economies
of T'ang China and the Uighur Empire." Journal of the Economic and Social History of the
Bentley, Jerry H. 1993. Old World Encounters: Cross-Cultural Contacts and Exchanges in Pre-
Modern Times. Oxford: Oxford University Press.
Blanton, Richard E. , Stephen A. Kowalewski, and Gary Feinman. 1992.
"The Mesoamerican World-System." Review 15:3(Summer):418-426.
Bornschier, Volker and Christopher Chase-Dunn (eds.) 1999 The Future of Global
Conflict London: Sage
Braudel, Fernand 1972 The Mediterranean and the Mediterranean World in the Age of Philip II.
New York: Harper and Row, 2 vol.
_____________. 1984. The Perspective of the World, Volume 3 of Civilization and Capitalism.
Berkeley: University of California Press
Chandler, David 1996 A History of Cambodia. Boulder, CO: Westview Press.
Chase-Dunn, C. 1988. "Comparing world-systems: Toward a theory of semiperipheral
development," Comparative Civilizations Review, 19:29-66, Fall.
Chase-Dunn, C and Thomas D. Hall 1993"Comparing World-Systems: Concepts and
Working Hypotheses" Social Forces 71:4(June):851-886.
____________________________1997 Rise and Demise: Comparing World-Systems Boulder,
CO.: Westview Press.
evolution” Pp. 97-119 in Patrick Manning and Barry K. Gills (eds.) Andre Gunder
Frank and Global Development, London: Routledge.
Chase-Dunn, C. , Thomas D. Hall and Peter Turchin. 2007 “World-Systems in the
Biogeosphere: Urbanization, State Formation, and Climate Change Since the Iron
Age.” Pp.132-148 in The World System and the Earth System: Global Socioenvironmental
Change and Sustainability Since the Neolithic, edited by Alf Hornborg and Carole L.
Crumley. Walnut Creek, CA: Left Coast Books.
Chase-Dunn, Chris, Roy Kwon, Kirk Lawrence and Hiroko Inoue 2011 “Last of the
hegemons: U.S. decline and global governance” International Review of Modern
Sociology 37,1: 1-29 (Spring).
Chase-Dunn, C. , Susan Manning and Thomas D. Hall 2000 “Rise and fall: East-West
synchronicity and Indic exceptionalism reexamined,” Social Science History. 24,4:727-
institutional materialist perspective,” International Journal of Comparative Sociology
Rebecca Álvarez, Alina Khan and Christian Jaworski 2013 “Semiperipheral Capitalist
City-States and the Commodification of Wealth, Land, and Labor Since the Bronze Age”
IROWS Working Paper #79 available at http://irows.ucr.edu/papers/irows79/irows79.htm
Chase-Dunn, C. and Dmytro Khutkyy 2015 “The evolution of geopolitics and imperialism
in interpolity systems” IROWS Working Paper # 93
Chase-Dunn, C and Bruce Lerro 2014 Social Change: Globalization from the Stone Age to the
Present. Boulder, CO: Paradigm
Chase-Dunn, C. Hiroko Inoue, Alexis Alvarez, Rebecca Alvarez, E. N. Anderson and Teresa
Neal 2015 “Urban uneven development: largest cities since the Late Bronze Age”
Presented at the annual conference of the American Sociological Association, Chicago,
August 24, 2015. IROWS Working Paper # 98 http://irows.ucr.edu/papers/irows98/irows98.htm
Data appendix for this paper is at http://irows.ucr.edu/cd/appendices/worregs/worregsapp.htm
Chase-Dunn, C. David Wilkinson, E.N. Anderson, Hiroko Inoue and Robert Denemark
2015 “Time-mapping globalization since the Bronze Age” IROWS Working Paper #
Chew, Sing C. 2001 World ecological degradation : accumulation, urbanization, and deforestation, 3000
B.C.-A.D. Walnut Creek, CA: Altamira Press
___________ 2007 The Recurring Dark Ages : ecological stress, climate changes, and system
transformation Walnut Creek, CA: Altamira Press
___________ 2014 “The Southeast Asian connection in the first Eurasian world economy,
200 BC- AD 500” Journal of Globalization Studies, Vol. 5 No. 1: 82–109
Coe, Michael D. 2003 Angkor and the Khmer Civilization. New
York: Thames and Hudson.
Ekholm, Kasja and Jonathan Friedman 1982 “’Capital’ imperialism and exploitation in the
ancient world-systems” Review 6:1 (summer): 87-110.
Elvin, Mark. 1973. The Pattern of the Chinese Past. Stanford: Stanford University Press.
Fitzpatrick, John. 1992. "The Middle Kingdom, the Middle Sea, and the Geographical Pivot
of History." Review XV, 3 (Summer): 477-521
Flynn, Dennis O. 1996 World Silver and Monetary History in the 16th and 17th Centuries.
Brookfield, VT: Variorum.
Frank, Andre Gunder 1998 Reorient: Global Economy in the Asian Age. Berkeley: University of
_________________ 2014 Reorienting the 19th Century: Global Economy in the Continuing Asian
Age. Boulder, CO: Paradigm Publishers.
Frank, Andre Gunder and Barry Gills 1994 The World System: 500 or 5000 Years? London:
Hall, Thomas D., Christopher Chase-Dunn and Richard Niemeyer. 2009 “The Roles of
Central Asian Middlemen and Marcher States in Afro-Eurasian World-System
Synchrony.” Pp. 69-82 in The Rise of Asia and the Transformation of the World-System,
Political Economy of the World-System Annuals. Vol XXX, edited by Ganesh K.
Trinchur. Boulder, CO: Paradigm Press.
Honeychurch, William 2013 “The Nomad as State Builder: Historical Theory
and Material Evidence from Mongolia” Journal of World Prehistory 26:283–321
Hui, Victoria Tin-Bor 2005 War and state Formation in Ancient China and Early Modern Europe.
Cambridge: Cambridge University Press.
_________________ 2008 “How China was ruled” China Futures, Spring, 53-65
Innis, Harold 1972  Empire and Communications. Toronto: University of Toronto Press.
Inoue, Hiroko 2014 “Settlement dynamics and empire dynamics: a comparative and
evolutionary world-systems perspective” Paper presented at the annual meeting of
the American Sociological Association, San Francisco, August 17.
Inoue, Hiroko, Alexis Álvarez, Kirk Lawrence, Anthony Roberts, Eugene N Anderson and
Christopher Chase-Dunn 2012 “Polity scale shifts in world-systems since the Bronze Age:
A comparative inventory of upsweeps and collapses” International Journal of Comparative Sociology
Inoue, Hiroko, Alexis Álvarez, Eugene N. Anderson, Andrew Owen, Rebecca Álvarez, Kirk
Lawrence and Christopher Chase-Dunn 2015 “Urban scale shifts since the Bronze
Age: upsweeps, collapses and semiperipheral development” Social Science History
Volume 39 number 2, Summer
Inoue, Hiroko Alexis Álvarez, E.N. Anderson, Kirk Lawrence, Teresa Neal, Dmytro
Khutkyy, Sandor Nagy and Christopher Chase-Dunn 2013 “Comparing World-
Systems: Empire Upsweeps and Non-core marcher states Since the Bronze Age”
Lattimore, Owen 1940 Inner Asian Frontiers of China. New York: American Geographical
Lenski, Gerhard 2005 Ecological-Evolutionary Theory. Boulder, CO: Paradigm Publishers
Lieberman, Victor. 2003. Strange Parallels: Southeast Asia in Global Context, c. 800-1830. Vol.
1: Integration on the Mainland. Cambridge: Cambridge University Press.
______________ 2009. Strange Parallels: Southeast Asia in Global Context, c. 800-1830. Vol 2:
Mainland Mirrors: Europe, Japan, China, South Asia, and the Islands. Cambridge:
Cambridge University Press.
Liu, Xinru and Lynda Norene Shaffer. 2007. Connections across Eurasia: Transportation,
Communication, and Cultural Exchange on the Silk Roads. New York: McGraw-Hill.
Liverani, Mario 2013 The Ancient Near East. New York: Routledge.
Mann, Michael. 1986. The Sources of Social Power, Volume 1: A history of power from the beginning
to A.D. 1760. Cambridge: Cambridge University Press.
McNeill, John R. and William H. McNeill 2003 The Human Web. New York: Norton.
Modelski, George 2003 World Cities: –3000 to 2000. Washington, DC: Faros 2000
______________ Tessaleno Devezas and William R. Thompson (eds.) 2008 Globalization as
Evolutionary Process: Modeling Global Change. London: Routledge
Morris, Ian 2010 Why the West Rules—For Now. New York: Farrer, Straus and Giroux
______ 2013 The Measure of Civilization. Princeton, NJ: Princeton University Press.
_______ and Walter Scheidel (eds.) The Dynamics of Ancient Empires: State Power from Assyria to
Byzantium. New York: Oxford University Press.
Neal, Teresa 2013 “The Sasanian empire and world-systems Research” Working Paper,
Department of History, University of California-Irvine
Pomeranz, Kenneth 2000 The Great Divergence: Europe, China and the Making of the Modern World
Economy. Princeton: Princeton University Press.
Sanders, William T., Jeffrey R. Parsons, and Robert S. Santley 1979 The Basin of Mexico:
Ecological Processes in the Evolution of a Civilization. New York: Academic Press,
Scheidel, Walter 2009 “From the “great convergence” to the “first great divergence”:
Roman and Qin-Han state formation” Pp. 11-23 in Walter Scheidel (ed.) Rome and
China: Comparative Perspectives on Ancient World Empires. New York: Oxford University
SESHAT : The Global History Data Bank http://seshatdatabank.info/
____________ and Sitta Von Reden (eds.) The Ancient Economy. New York: Routledge.
Sherratt, Andrew G. 1993a. "What Would a Bronze-Age World System Look Like? Relations
Between Temperate Europe and the Mediterranean in Later Prehistory."
Journal of European Archaeology 1:2:1-57.
_____. 1993b. "Core, Periphery and Margin: Perspectives on the Bronze Age." Pp. 335-345 in
Development and Decline in the Mediterranean Bronze Age, edited by C. Mathers and S. Stoddart.
Sheffield: Sheffield Academic Press.
_____. 1993c. "Who are You Calling Peripheral? Dependence and Independence in European
Prehistory." Pp. 245-255 in Trade and Exchange in Prehistoric Europe, edited by C. Scarre and F.
Healy. Oxford: Oxbow (Prehistoric Society Monograph).
_____. 1993d. "The Growth of the Mediterranean Economy in the Early First Millennium BC."
World Archaeology 24:3:361-78.
University Press. eMap : Atlas : Document : English : 2nd impression. Chicago, Ill. :
Digital South Asia Library, Center for Research Libraries
Taagepera, Rein 1978a "Size and duration of empires: systematics of size" Social Science
______ 1978b "Size and duration of empires: growth-decline curves, 3000 to 600 B.C."
Social Science Research, 7 :180-96.
______1979 "Size and duration of empires: growth-decline curves, 600 B.C. to 600 A.D."
Social Science History 3,3-4:115-38.
_______1997 “Expansion and contraction patterns of large polities: context for Russia.”
International Studies Quarterly 41,3:475-504.
Tambiah, Stanley J. 1977 "The galactic polity: the structure of traditional kingdoms in
Southeast Asia", Anthropology and the Climate of Opinion, Annals of the New York
Academy of Sciences 293: 69–97
Teggart, Frederick J. 1939 Rome and China: A Study of Correlations in Historical Events Berkeley:
University of California Press.
Thompson, William R and Kentaro Sakuwa 2013 “Was Wealth Really Determined in 8000 BCE,
1000 BCE, 0 CE, or Even 1500 CE? Another, Simpler Look” Cliodynamics 4,1: 2-29
Tilly, Charles. 1990. Coercion, Capital, and European States, AD 990-1990. Cambridge, MA:
Turchin, Peter 2011 “Strange Parallels: Patterns in Eurasian Social Evolution” Journal
of World Systems Research 17(2):538-552
Turchin, Peter, Jonathan M. Adams, and Thomas D. 2006. “East-West Orientation of
Historical Empires and Modern States.” Journal of World-Systems Research. 12:2(December):218-229.
___________ and Sergey Gavrilets 2009 “The evolution of complex hierarchical societies”
Social Evolution & History, Vol. 8 No. 2, September: 167–198.
______________Thomas E. Currie, Edward A.L. Turner and Sergey Gavrilets 2013
Turchin, Peter, Rob Brennan, Thomas E. Currie, Kevin C. Feeney, Pieter François, Daniel
Hoyer, J. G. Manning, Arkadiusz Marciniak, Daniel Mullins, Alessio Palmisano,
Peter Peregrine, Edward A. L. Turner, Harvey Whitehouse. 2015.
“Seshat: The Global History Databank” Cliodynamics 6: 77–107
Wallerstein, Immanuel 2011  The Modern World-System, Volume 1. Berkeley: University
of California Press.
Wilkinson, David 1987 "Central Civilization." Comparative Civilizations Review 17:31-59.
______________1991 "Core, peripheries and civilizations." Pp. 113-166 in Christopher
Chase-Dunn and Thomas D. Hall (eds.) Core/Periphery Relations in Precapitalist Worlds,
Boulder, CO.: Westview.
_______________1992a "Decline phases in civilizations, regions and oikumenes." A paper
presented at the annual meetings of the International Studies Association, Atlanta,
GA. April 1-4.
______________ 1992b "Cities, civilizations and oikumenes:I." Comparative Civilizations
Review 27:51-87 (Fall).
_______________ 1993 “Cities, civilizations and oikumenes:II” Comparative Civilizations
Review 28: 41-72.
_______________2004 The Power Configuration Sequence of the Central World System, 1500-700 BC
Journal of World-Systems Research Vol. 10, 3.
Wilkinson, Toby C., Susan Sherratt and John Bennet 2011 Interweaving Worlds: Systemic Interactions in
Eurasia, 7th to 1st Millennia BC. Oxford: Oxbow Books.
Wohlforth, William C., Richard Little, Stuart J. Kaufman, David Kang, Charles A Jones,
Victoria Tin-Bor Hui, Arther Eckstein, Daniel Deudney and William L Brenner 2007
“Testing balance of power theory in world history” European Journal of
International Relations 13,2: 155-185.
Wolf , Eric 1997 Europe and the People Without History, Berkeley: University of California
Wong, R. Bin 1997 China Transformed: Historical Change and the Limits of European Experience.
Ithaca: Cornell University Press.
 Use of the word “evolution” still requires explanation. We mean long-term patterned change in social structures, especially the development of complex divisions of labor and hierarchy. We do not mean biological evolution, which is a very different topic, and neither do we mean “progress.”
 The term “settlement” includes camps, hamlets, villages, towns and cities. Settlements are spatially bounded for comparative purposes as the contiguous built-up area.
 We use the term “polity” to generally denote a spatially-bounded realm of sovereign authority such as a band, tribe, chiefdom, state or empire. Our study of polity size upsweeps is presented in Inoue et al (2012).
 Thus we are both continuationists and transformationists.
 The project is the Polities and Settlements Research Working Group at the Institute for Research on
World-Systems at the University of California-Riverside. The project web site is at http://irows.ucr.edu/
 But if we read especially Frank and Gills as studying the continuities of the Central PMN and the Central PGN, as discussed below, much of their analysis is quite valuable.
 See also http://en.wikipedia.org/wiki/Chronology_of_the_ancient_Near_East and Modelski (2003: 202).
 The idea of the Central System is derived from David Wilkinson’s (1987) definition of “Central Civilization.” It spatially bounds a system in terms of a set of allying and fighting polities. Various terms are conventionally used to designate networks of fighting and allying polities. We prefer political/military network (PMN) but this means approximately the same thing as “international system,” “interstate system” and “interpolity system.” The Central Political-Military Network is that interpolity network that emerged when the Mesopotamian and Egyptian PMNs became directly connected with one another in about 1500 BCE (see below). The Central PMN expanded in waves until it came to encompass the whole Earth in the 19th century CE. Because it was an expanding system, its spatial boundaries changed over time. We follow David Wilkinson’s decisions about when and where the Central PMN expanded. The merger of the Mesopotamian and Egyptian PMNs began as a result of Eighteenth Dynasty Egypt’s invasions, conquests, and diplomatic relations with states of the Southwest Asian (Mesopotamian) system -- first of all Mitanni, then the Hittites, Babylon, and Assyria. The signal event was Thutmosis I’s invasion of Syria in 1505 BCE. The fusion of these networks began then but enlarged and intensified until 1350 BCE. Thutmosis III’s many campaigns in Syria and the establishment of tributary relations, wars and peace-making under Amenhotep II, as well as the peaceful relations and alliance with Mitanni by Thutmosis IV, eventually led to Egyptian hegemony under Amenhotep III (Wilkinson pers. comm. April 15, 2011). The final linking of the South Asian PMN with the Central PMN was begun by the incursion of Mahmud of Ghazni in 1008 CE. Alexander of Macedon’s earlier incursion in the 4th century BCE had been a temporary connection between the Central and the South Asian PMNs that ceased after the Greek conquest states in South Asia had been expelled. The connection was made permanent by Mahmud of Ghazni. After 1850 CE the East Asian PMN was engulfed by the Central PMN when European states established treaty ports in East Asia.
 The boundary between Southeast Asia and South Asia is the Burma/Bangladesh border.
 An earlier regional typology was originally developed to study largest cities (Chase-Dunn and Manning 2002), but in this paper we also consider largest polities, which has required us to pay more attention to Central Asia. We have also added the Americas.
 Timing of incorporation of world regions into the
Central PMN: Africa: 1500BCE; South West Asia: 1500BCE ; Europe: 700BCE ; Central Asia & Siberia: 0 CE
(30CE--Kushan & Rome interaction)
South Asia: 1000CE ; South East Asia: 1500CE ; South America and Caribbean: 1500CE ; North and Central America: 1500 CE; Oceania: 1900 CE
 We were able to code some earlier estimates for South Asia based on Schwartzberg’s Atlas (1992) and we have used other atlases and historical sources to estimate polity sizes for the 100-year time points we are studying here. We are in the process of producing a comprehensive annotated bibliography of historical atlases that indicates their content regarding maps that show the territorial sizes of polities.
 The comparative world-systems perspective developed by Chase-Dunn and Hall (1997) contends that semiperipheral capitalist city-states (specialized trading states in semiperipheral locations in the interstices between large tributary states and empires) were the main agents that encouraged commercialization and the production of commodities in the Bronze and Iron Ages. See also Chase-Dunn et al (2013).
It should be noted that the Romans were never able to conquer the Parthian empire and so Rome was never the “universal empire” that it claimed to be. But Scheidel’s point stands.
 Support for this notion that the structure of transportation and communication is an important cause of the formation of empires comes from the comparison between Mesopotamia and Egypt. Egypt with a single river valley was brought under the control of a single polity much more quickly than was the two-river system in Mesopotamia. This may have been due to the relative ease of controlling transportation and communications in a linear system. But this example, arguing for the ease rather than the difficulty of communications, goes against Scheidel’s idea that Mediterranean should have maintained a decentralized state system.