Shaking Legitimacy: The Impact of Earthquakes on Conflict in Historical China

This paper examines the causal effect of political legitimacy on stability, using the historical case of Imperial China. Chinese rulers ascribed their legitimacy to a heavenly mandate. Calamities like earthquakes were considered to be a sign of weakened approval, making quakes a proxy for a negative legitimacy shock. I use quake-induced minor shaking (i.e., strong enough to be felt, but too weak to cause material damage) to demonstrate that legitimacy shocks cause more conflicts. I examine whether quakes serve as a coordination device to overcome collective action problems.