The burgeoning literature on civil conflicts seldom considers why some civil wars are so much deadlier than others. This article investigates that question using a new data set of the number of combat deaths in internal conflicts from 1946 to 2002. The first section presents descriptive statistics on battle deaths by era, conflict type, and region. The article then tests state strength, regime type, and cultural characteristics as predictors of the number of combat deaths in civil war. The determinants of conflict severity seem to be quite different from those for conflict onset. Democracy, rather than economic development or state military strength, is most strongly correlated with fewer deaths; wars have also been less deadly on average since the end of the cold war. Religious heterogeneity does not explain the military severity of internal violence, and surprisingly, ethnic homogeneity may be related to more deadly conflicts.
Key Words: civil war • battle