Silk Roads to Riches: Persistence Along an Ancient Trade Network

The Silk Roads were a decentralized network of trade routes that connected ancient cities across Eurasia. Goods, ideas, people, and technology moved along the roads for over 1,500 years. Using a detailed georeferenced map of the entire trade network, this paper finds that areas within 50 KM of the historic location of the Silk Roads have higher levels of economic activity today. The persistent effect of proximity to the ancient trade network is associated with increased access to modern transportation infrastructure and the historical diffusion of technology along the routes but cannot be explained by differences in contemporary or historical levels of population density. This analysis is complemented by individual-level data from 22 countries; we find that districts with populations closest to the Silk Roads have higher rates of inter-group marriage, suggesting a weakening of social boundaries between groups that might possess differential technological knowledge.