It’s commonly assumed that oil is a major reason countries go to war. Researchers have now confirmed this assumption, showing that the likelihood of a third country butting its nose into a civil war is related to the amount of petroleum reserves in a country.

Petros Sekeris from the University of Portsmouth, Vincenzo Bove from the University of Warwick, and Kristian Skrede Gleditsch from the University of Essex in Great Britain looked at 69 countries that experienced civil conflicts between 1945 and 1999. They found that about two-thirds of these wars saw intervention by another country or outside organization—and that the most common reason for this intervention had to do with oil “over and above historical, geographical or ethnic ties.”

The research also revealed that the more oil a country had, the more likely a third party would be to enter the conflict, and that those intervening in the civil wars were likely to be big importers of oil.

“We found countries producing lots of oil or those with higher reserves (and considerable market power) were more likely to attract military support,” Sekeris and Bove wrote at The Conversation.

“Most often this was to preserve oil prices on international markets. Indeed, there were on average more interventions in periods when there were only a few big oil producing countries and thus reduced competition (and more stable prices),” they added.

While the research stopped at 1999, more recent examples of oil-induced military intervention can be seen in the U.S. decision to attack ISIS in northern Iraq, where oil development is important, according to Homeland Security News Wire.

-Noel Brinkerhoff

To Learn More:

Are Crude Conspiracies Right? Research Shows Nations Really Do Go To War Over Oil (by Petros Sekeris and Vincenzo Bove, The Conversation)

Need For Oil the Most Important Reason for Interfering in Another Country’s War (Homeland Security News Wire)

“Oil Above Water”: Economic Interdependence and Third Party Intervention (by Petros Sekeris and Vincenzo Bove) (pdf)