Ethnicity and the spread of civil war

Civil wars critically hinder a country's development process. This paper shows that civil wars can also have severe international consequences. Anecdotal evidence highlights that civil wars sometimes spill over international boundaries. Using a more rigorous econometric approach we provide evidence that conflict spillovers are indeed quantitatively very important. Also, they are context dependent. Ethnicity in particular plays a key role in the spread of civil war. Only ethnic civil wars spill over, and only along ethnic lines. We do not find evidence that poor, ethnically heterogenous, or less populous countries are more or less susceptible to spillovers. Ethnic links to a neighbor at ethnic civil war increase the probability of an outbreak of ethnic civil war at home by 6 percentage points.