How persistent is armed conflict?
We assess the degree of persistence in armed conflict in particular places over the last two centuries, asking in addition if conflict-ridden places have durable features – social, demographic or geographical – that explain persistence, or whether armed conflict at one time has a causal effect on propensity for armed conflict at later times. For all types of war in the Correlates of War data, we code the territories on which the armed conflict occurred. The data reveal significant levels of persistence in territories that experienced extra-state (imperial and colonial) and non-state wars in an earlier era. Exogenous features such as geography and pre-1800 demography are important in explaining where conflicts persist. However there remains significant persistence controlling for geographic and demographic features. In particular, extra-state wars before 1945 are strongly related to civil war after 1945. This persistence does not appear to arise from the long-run enmity of particular groups that fight repeatedly over centuries. We conjecture that imperial and colonial wars may have been more likely in territories where there were more and/or more developed pre-colonial state structures, and that either the persistence of these structures or changes in them brought about by the violent encounters raised civil war risks after 1945.