Feeding the Frontier: Military-Agrarian Systems and Resource Competition in the Western Peripheries of the Tang Empire

This paper explores land use and resource control in the Tang Empire’s western peripheries, focusing on the western Loess Plateau and the northeastern Tibetan Plateau. By the seventh century, a growing military presence in the region led to increased competition for land. Both the Tang and Tibetan empires exploited the regional agropastoral economies to support their expanding standing armies and livestock, especially horses, likely facilitated by favorable relatively warm and moist conditions that may have increased both crop potential and pasture productivity. Tang accounts offer insights into the competition for land control and use as the landscape shifted from predominantly pastoral to increasingly agricultural to support the expanding armies. Here, using historical sources and reconstructions of farming landscapes, I examine the Tang military-agrarian economy in the western Loess Plateau. I argue that the rising demand for land intensified competition and pushed expansion westward into the arid areas of the northeastern Tibetan Plateau. Tibetan advances in the mid-eighth century led to a rapid contraction of Tang control in the western territories. While territorial losses are often attributed to military strategic choices, I argue that structural weaknesses in a military-agrarian system within a marginal and fragile ecological zone were also a decisive factor. Both empires likely struggled to sustain the supply infrastructure required to support large standing armies over time. The second part of the paper examines Tang’s response to territorial losses, including policies to address resource shortages, restore transport infrastructure, reclaim farmland, and mobilize labor.