Winter is Coming : The Long-Run Effects of Climate Change on Conflict, 1400-1900

We investigate the long-run effects of cooling on conflict. We construct a geo-referenced and digitized database of conflicts in Europe, North Africa, and the Near East from 1400-1900, which we merge with historical temperature data. We show that cooling is associated with increased conflict. When we allow the effects of cooling over a fifty-year period to depend on the extent of cooling during the preceding period, the effect of cooling on conflict is larger in locations that experienced earlier cooling. We interpret this as evidence that the adverse effects of climate change intensify with its duration