This chapter addresses the question of whether oil causes revolutionary government, that is, whether revolutions are more likely to occur in petrostates than in non-petrostates. This question is important because up to this point, I have treated the emergence of a revolutionary government as an independent, exogenous event. If this premise is not true, it could significantly alter our understanding of how oil leads to international conflict. Although a comprehensive investigation into the causes of revolutions is far outside the scope of this book, some exploration of the specific relationship to oil income is well worth the effort.

I first consider the question theoretically. I argue that while the idea is plausible, the extant literature does not provide a simple or unambiguous prediction about how oil might affect the incidence of a revolutionary government. The question therefore begs for empirical analysis. I then present the results of an initial investigation using both quantitative and qualitative approaches, to probe whether there is evidence of a causal link. Finding no such evidence, I conclude that oil and revolutionary governments can be treated as variables that are (mostly) independent of each other.