Toward a Comparative Study of Imperial Metabolism
The vast literature on the archaeology and history of empires contains a growing body of quantitative data on land use, tribute flows, and the organization of labor that could be used for a systematic, comparative analysis of the material metabolism of imperial projects.
This chapter can merely suggest a possible direction for such work to pursue, building on some methodological experiments in quantifying asymmetric transfers of embodied labor and embodied land.[1090] Labor and land can be translated as (human) “time” and (natural) “space” and their appropriation by imperial power centers understood as a societal redistribution of time and space. Later in this chapter we shall see how modern “technology” fits into this picture as a recent version of time-space appropriation, but the argument will make more sense if it is grounded in a long-term history of imperialism.The list of imperial projects to be briefly considered here begins with two distinct and foundational Old World empires, Han China (206 bce-220 ce) and Rome (241 bce-476 ce). These imperial expansions are then compared with the two most prominent New World examples, the Inca (1438-1532) and the Aztec (14281519). We shall next consider the establishment of two trans-Atlantic empires that were largely based on connecting Old and New World resource flows, the Spanish (1492-1780) and the British (1600-1947). Finally, we shall discuss continuities and discontinuities in imperial strategies through more than two millennia of world history, from ancient Rome to the United States. How can all these strategies be compared in terms of flows of appropriated energy, land, and labor, and how can they be differentiated in terms of ideologies and institutions?
Han China (206 bce-220 ce)
After a civil war which ended the former Qin dynasty, the Han dynasty, founded in 206 bce, consolidated imperial control over a Chinese population of around 60 million people and a territory extending about four million square kilometers.[1091] The metabolism of the empire was primarily based on the extraction of agricultural tribute, mostly in the form of grains such as rice, wheat, and millet.
Based on an estimated average carrying capacity of two persons per hectare, the agricultural area can be roughly calculated at around 300,000 square kilometers. Oxen and water buffalo were used as draft animals, but all other work was conducted by humans. Along with grain, raw materials such as cotton and timber, as well as precious items such as jade, corals, ivory, pearls, and gems, were imported to imperial centers, which in turn exported and redistributed textiles (including silk), grain, incense, spices, medicines, and ornaments. The main forms of capital investments were hydraulic infrastructures for agriculture, transports (roads, canals), ceremonial architecture, and an army numbering several hundred thousand warriors. In ideological terms, imperial power was founded on the divinity of the royal dynasty and the perception of the empire as protection against enemies. In material terms, the fundamental rationale of the ancient Chinese empire was to use military coercion and religious devotion to extract labor and food energy through tens of millions of peasants on hundreds of thousands of square kilometers of agricultural land.Rome (241 BCE-476 ce)
By 241 bce, the former city-state of Rome had begun to expand beyond the Italian Peninsula by conquering the islands of Sicily, Sardinia, and Corsica.[1092] It then proceeded to conquer the Carthaginian territories in northern Africa and Iberia, consolidating an empire which controlled the Mediterranean and much of what is now Europe for several centuries, until the fall of Western Rome, traditionally set to 476 ce. The total population of the empire was around 60-75 million people in 150 ce, of which around one million lived in the city of Rome itself. Like Han China, it was basically an agrarian empire collecting tribute in grain, notably from Egypt. The 2.7 million hectares of agricultural land in Egypt supported an estimated 7.5 million people, suggesting a carrying capacity of 2.7 people per hectare.
Unlike China, however, the Roman Empire depended heavily on maritime shipping across the Mediterranean. Instead of the Chinese rivers and canals, Rome relied on the sea for bulk deliveries of grain to its center, perhaps as much as 400,000 tons in some years.[1093] When imports were at their height, only around 10 percent of the wheat consumed in the city of Rome was grown in Italy.[1094] Another difference was the central significance of slavery, an institution inherited from ancient Greece.To a large extent, slaves were war captives from peripheral areas of the empire. It has been suggested that it was in part because they became increasingly expensive in the early centuries ce that some of their labor was replaced by water-mills.[1095] Oxen were used as draft animals. Wine and olive oil were traded throughout the Mediterranean. Major capital investments were made in farmland, roads, architecture (including aqueducts), armies, and naval fleets. Although water-mills and sailing ships represented alternative sources of energy, the Roman Empire was primarily based on the extraction of food energy from conquered territories and the exploitation of peasant and slave labor. Christianity became the state religion in the fourth century. In the year 395 the empire was split into a Western and an Eastern (Byzantine) half, the latter centered on the city of Constantinople. The Western half fell apart during the fifth century, but the Byzantine Empire survived for another millennium, until Constantinople was conquered by the Ottomans in 1453.
Inca(1438-1532)
After a decisive victory over the neighboring Chanka polity in 1438, the kingdom of Cuzco in the southern Andes rapidly conquered the Andean highlands and Pacific coast of South America, from northern present-day Ecuador to central Chile.[1096] Military force remained a central means of expansion, but several provinces of the Inca Empire were integrated through diplomatic persuasion.
At its height, prior to the Spanish conquest in 1532, the population of the empire may have been close to 12 million people. The majority were peasants and llama pastoralists, the main staples being potatoes (in higher altitudes) and grains such as maize and quinoa. Estimates of the productivity of intensive raised-field potato cultivation in the Titicaca Basin suggest a local carrying capacity of up to four people per hectare. Because there were no draft animals, all agricultural labor was undertaken by humans. The Inca court established a redistributive system of tribute represented as relations of mutual benefit, in which common people delivered labor and military service in exchange for ceremonially distributed gifts of maize beer, cloth, and ornaments. In addition to the maintenance of agricultural terraces, irrigation canals, armies, roads, and ceremonial architecture, tribute was invested in a system of warehouses storing food and cloth for redistribution in times of need. Imperial ideology represented the Inca emperor as the divine son of the Sun and the source of agricultural productivity, which meant that the delivery of tribute to him was perceived to be compensation for harvests and protection against famine. Investments in architecture and infrastructure increased the capacity of the imperial elite to extract labor, food, and materials from the territories over which it had gained control.Aztec (1428-1519)
Following the defeat of neighboring Azcapotzalco in 1428 and certainly by the time of the Spanish conquest of 1519, the Aztec polity centered on the city of Tenochtitlan had conquered much of what is now Mexico.[1097] About 250,000 hectares of raised fields and other intensively farmed land in the Basin of Mexico provided food for about one million people, suggesting a carrying capacity of around four people per hectare in the core area, a figure identical to the one for the Titicaca Basin. The main agricultural staple was maize.
As in the Andes, there were no draft animals. In fact, in ancient Mexico there were not even any pack animals like the Andean llama, which meant that all tribute and merchandise had to be carried by humans. The Mesoamerican area was considerably more commercialized than the Andes, and the political consolidation of Aztec hegemony was less formalized. Whether the extraction of goods from peripheral areas was perceived as tribute or trade seems unclear, since the emperor's tribute-collectors were merchants and much of the transfer of goods occurred at markets. Major items of trade and tribute included obsidian, cotton textiles, ceramics, feathers, gold, jade, turquoise, bronze, and cacao. Cacao beans and cotton textiles frequently served as currencies in market transactions. The Aztec Empire illustrates how the extraction of labor-power and natural resources for purposes of accumulation in core areas can occur largely through market (“non-administered”) exchange, even in pre-modern contexts.Spanish (1492-1780)
The Iberian peninsula was integrated into the Umayyad caliphate in 711 and remained partly Muslim territory until 1492, when the Habsburg dynasty defeated the last caliph of Granada and attempted (as Charlemagne had done seven centuries earlier) to resurrect the Western Roman Empire.[1098] The ideology of conquest and unification was strongly grounded in Christian theology. Blocked by Muslim polities, which now controlled most of the Mediterranean, the Iberian rulers extended their interests westward, trading along the African coasts and establishing sugarcane plantations on Madeira, the Azores, the Canary Islands, and in the Caribbean. Having sponsored exploration of the Caribbean since Columbus's first voyage in 1492, the Spanish Crown began extracting bullion from the Aztecs in the 1520s and from the Incas in the 1530s. By the end of the sixteenth century, Spanish silver mines in the New World yielded about 85 percent of the world's silver.
However, the Spanish Crown was heavily indebted, and much of the wealth ended up in the Netherlands, which was claiming independence from Habsburg Spain and Portugal at this time. Because of the strong demand for silver in China and India, the Dutch East India Company in the early seventeenth century was thus well equipped to assume control over the European trade in spices and other merchandise from Indonesia and the Indian Ocean. Previously controlled by the Portuguese, who in 1497 had rounded Africa, this trade largely passed into Dutch hands over the course of the seventeenth century. Meanwhile, Portugal controlled much of the Atlantic trade in African slaves bound for its own sugar plantations in Brazil, as well as for Spanish plantations in the rest of the Iberian New World. By the mid-eighteenth century, the Spanish colonial territories in the New World encompassed western South America (most of the continent except Portuguese Brazil), almost all of Mesoamerica and the Caribbean, and western North America. These territories exported several agricultural products, such as sugar, tobacco, cacao, and hides, but precious metals remained most important. Spain itself provided its colonies with iron, mercury (for refining silver), wine, and olive oil, as well as luxury goods like textiles and porcelain that often had a nonSpanish origin. Spain also imported grain and timber from northern Europe. Its main capital investments were in ships, armies, and ceremonial architecture. The use of wind energy to propel its sailing vessels was a crucial complement to the muscle energy of humans, horses, and oxen in maintaining the metabolism of the empire. During the second half of the eighteenth century, the Spanish Empire experienced several major rebellions, such as the Tupac Amaru revolt aiming to resurrect Inca power in Peru in 1780.British (1600-1947)
In the year 1600, the British East India Company was granted monopoly on English trade east of Africa.[1099] Although unable to compete with its Dutch counterpart in Southeast Asia, it established successful relations with the Mughal Empire in India and soon exported Indian textiles, silk, indigo, saltpeter, and tea to Europe. Similar companies organized British expansion in North America and Africa. The Virginia Company (founded 1606) thus financed the establishment of English settlements in North America, beginning with Jamestown in 1607; the Royal Africa Company (founded 1663) organized the trade in slaves for the British plantation colonies in the Caribbean; and the Hudson's Bay Company (founded 1670) controlled the North American fur trade. The island of Jamaica became an important British colony in 1655. In the seventeenth century, 60 percent of the people who crossed the Atlantic to live in the British, Spanish, Portuguese, French, and Dutch colonies in the New World were African slaves, a figure that in the next century rose to 75 percent. The slave trade and plantation system created demand for food exports from the British colonies in North America as well as for cotton textiles exported from Britain,[1100] while industrial workers in England derived a significant share of their food energy from Caribbean sugar mixed with tea from China and India.[1101] The imports to England of cotton, sugar, and other land-intensive products from the New World colonies were part of the so-called triangular trade through which British merchants exchanged cotton cloth and other manufactures for West African slaves, which were then shipped across the Atlantic and sold in the colonies. The mechanization prompted by the market demand for textiles likewise offered powerful new vehicles for transport and military conquest, most notably trains and steamboats. Although colonial territories in North America (the future United States of America) achieved independence from Britain in 1783, the empire continued to expand. In the early twentieth century, the British Empire encompassed around 650 million people and about 35 million square kilometers. Much of this territory remained part of the empire until the mid-twentieth century, when a number of important former colonies achieved independence, notably India in 1947 and several African nations in the 1960s. It was in the core of the British Empire that the “Industrial Revolution” occurred in the late eighteenth and early nineteenth centuries. This signified a new kind of capital investment alongside the fields, roads, canals, armies, ships, and architecture of earlier empires: capital accumulation in the British Empire also included factories, railroads, and steamships. The strategy of industrial imperialism established in Britain was to be adopted and expanded by its former colonies in North America, as the United States emerged as an imperial power in the mid-twentieth century. What these new investments in “technology” actually meant in terms of imperial metabolism is the topic of the next section.