Economic Diversification Supported the Growth of Mongolia’s Nomadic Empires

Abstract

Populations in Mongolia from the late second millennium B.C.E. through the Mongol Empire are traditionally assumed, by archaeologists and historians, to have maintained a highly specialized horsefacilitated form of mobile pastoralism. Until recently, a dearth of direct evidence for prehistoric human diet and subsistence economies in Mongolia has rendered systematic testing of this view impossible. Here, we present stable carbon and nitrogen isotope measurements of human bone collagen, and stable carbon isotope analysis of human enamel bioapatite, from 137 well-dated ancient Mongolian individuals spanning the period c. 4400 B.C.E. to 1300 C.E. Our results demonstrate an increase in consumption of C 4 plants beginning at c. 800 B.C.E., almost certainly indicative of millet consumption, an interpretation supported by archaeological evidence. The escalating scale of millet consumption on the eastern Eurasian steppe over time, and an expansion of isotopic niche widths, indicate that historic Mongolian empires were supported by a diversification of economic strategies rather than uniform, specialized pastoralism. Mongolian empires, such as the Xiongnu and Mongols, are some of the most renowned imperial entities in public and academic thought. This is, in part, due to their historical portrayal as highly mobile, predatory horseback polities with a specialized dairy and meat-based economy 1-4 , an image that is perpetuated in cinema, novels, and documentaries alike. While such stereotypes likely arose from the hyperbolized accounts of neighboring adversaries, starting with the Han, who fought against the Xiongnu 5 , they have persisted and now pervade academic evaluations of the economic basis of these ancient peoples. The modern economic focus on pastoralism in rural areas of Mongolia today is frequently viewed as a relic of the past and has been drawn upon to interpret the often-fragmentary archaeological record of this region 6,7 , although ethnoarchaeological approaches often ignore the role of urban markets and motorized transport in modern mobile pastoralism. The view of uniformly specialized pastoral economies has also furthered the scholarly fascination with historical Mongolian populations, resurrecting the long-standing question of whether an empire can meet the costs and challenges of long-term political and economic organization in the absence of grain surpluses 6,7. Empires are, however, inherently complex and, by definition, extend their control over multiple societies, cultures, and economies, as well as heterogeneous landscapes 8-10. Crop surplus has traditionally been viewed as an essential component of stable political entities and complex imperial food production and procurement systems are often oversimplified by historians and archaeologists, leading to their characterization as single-resource systems (such as maize for the pre-Columbian empires of South America). Refined analyses generally reveal diverse and dynamic economies supporting imperial expansions, which draw together a variety of food sou...

A Dynamic 6,000-Year Genetic History of Eurasia’s Eastern Steppe

“…Similar to Slab Graves, recent analysis of proteins in human dental calculus has confirmed the utilization of ruminant and horse milk among those at Chandman Mountain (Wilkin et al, 2020a). Isotopic studies have also shown that some Uyuk communities, including at Chandman Mountain, had a significant amount of millet in their diet (Murphy et al, 2013;Wilkin et al, 2020b). This links them to agropastoralist cultures of the Western Steppe, where the intensification of millet cultivation occurred during the second millennium BCE (Ventresca Miller and Makarewicz, 2019).…”

“…High quality genetic data was successfully generated for 214 individuals and was used for population genetic analysis (Table S2A). Subsistence information inferred from proteomic analysis of dental calculus has been recently published for a subset of these individuals (n = 32; Wilkin et al, 2020a), and stable isotope analysis of bone collagen and enamel (n = 137) is also in progress (Wilkin et al, 2020b); together, these data allow direct comparison between the biological ancestry of specific archaeological cultures and their diets, particularly with respect to their dairy and millet consumption. Below, we provide an overview of the geography and ecology of the archaeological sites in this study, as well as their temporal and cultural context.…”

Prehistoric agriculture and social structure in the southwestern Tarim Basin: multiproxy analyses at Wupaer

“…Archaeobotanical data have also been used to demonstrate an increased prevalence of water-demanding crops in southern Central Asia 79 , and more intensive irrigation systems may have existed from the Murghab Oasis 81 , to Khorezm 82 , and Semirechye 77 in the late first millennium BC. Wilkin et al 83 recently suggested that the introduction of millet and possibly cereal farming in Mongolia may have played a role in the development of more complex social systems there as well. The apparent switch to more heavily irrigated crops during the key transitional period in the oases on the peripheries of the Taklimakan Desert, further support the growing evidence that illustrate a link between more elaborate and hierarchical political systems and farming in Central Asia 43 .…”

An Imagined Past?

“…The second publication noted that millet cultivation, as part of an agropastoral economy, became widespread during the Xiongnu period (ca. 200 BC-AD 100; Wilkin et al 2020b). In addition, analysis of cementum annulations from Begash and Tasbas recently demonstrated that people and their animals were using those places throughout the year, rather than as seasonal campsites (Schmaus, Doumani Dupuy, and Frachetti 2020).…”

“…Forthcoming work incorporates archaeological and textual evidence to highlight how the Xiongnu Empire controlled landscapes outside of modern-day Mongolia and propelled interactions along the Silk Road (Miller, forthcoming). For example, isotopic analysis suggests that Mongolia's first herders may have subsisted on a diet largely of domesticated livestock and wild resources, but that millet and domesticated plants became widespread by the time of the first empire, the Xiongnu (Wilkin et al 2020b). This research will allow future scholars to contextualize the role of specialized pastoralism in the cases where it is observed archaeologically.…”