Why We Fight

This paper provides evidence of the long-run effects of a permanent increase in agricultural productivity on conflict. We construct a newly digitized and geo-referenced dataset of battles in Europe, the Near East, and North Africa from 14001900 ce and examine variation in agricultural productivity due to the introduction of potatoes from the Americas to the Old World after the Columbian Exchange. We find that the introduction of potatoes led to a sizeable and permanent reduction in conflict.

The Long-Run Effects of Agricultural Productivity on Conflict, 14001900