Walls at the Edge of the World: Nomadic Dynasties and Border Fortifications in Medieval Mongolia

Why do states and empires build frontier walls, and what purposes do these costly monuments serve? Between the tenth and thirteenth centuries CE, much of East and Central Asia was ruled by dynasties founded by nomadic groups. Three of these, the Liao (907–1125), Jin (1115–1234), and Western Xia (1038–1227), constructed elaborate systems of border fortifications stretching some 4,000 km across remote and sparsely populated steppe and desert regions. Despite their monumental scale, these structures receive little attention in historical sources and have attracted limited archaeological investigation. 

In this talk, I draw on my ERC-funded project, “The Wall: People and Ecology in Medieval Mongolia and China,” which integrated archaeological, historical, and palaeoclimatic research to investigate the chronology, structure, and functions of these frontier systems. I explore what motivated the so-called “nomadic dynasties” to invest in their construction and maintenance, and what these monuments reveal about the relationship between imperial power, human mobility, and environmental change.