What causes civil war?

There are three types of theories on the origins of civil war:

  • Grievance: Grievance based theories focus on economic inequality and ethnic difference as sources of conflict.
  • Greed: Greed-based theories focus on the desire by groups to capture sources of revenue, including state control of oil fields and other natural resources.
  • Resources: Resource-based theories focus on militant groups’ ability to organize and fund themselves.


Grievance-based theories focus on why people are so angry that they are willing to go to war.   High levels of poverty in a country (low GDP) and high levels of inequality are both correlated with higher levels of civil wars internationally.  Economic grievances can provide a way for rebel leaders to organize and motivate followers, as Ted Gurr argued in Why Men Rebel.  Class conflict contributed to civil war in Angola, Nepal, and Central America (Guatemala, El Salvador, and Nicaragua), among other places.

Ethnic diversity can also provide a source of grievance, especially when combined with economic inequality.  These arguments are most commonly associated with David Horowitz, who wrote the seminal book Ethnic Groups in Conflict.  While scholars do not find a statistical correlation between measures of ethnic fractionalization and civil war, there is some evidence that having a large dominant ethnic group or a small minority group control the government to the exclusion of other groups contributes to conflict.

Ethnic diversity appears to matter when it provides the foundation for an unequal distribution of resources between groups (when the Syrian government favors the Alewite minority over Sunnis and Kurds, for example) and when it becomes the means to mobilize groups for political ends. Daniel Posner, in his article on “The Political Salience of Cultural Difference,” shows that differences between ethnic groups alone don’t lead to political conflict.  Only under certain circumstances (Posner points to the relative size of a group in the country) does ethnicity become a source of prejudice and political discord.

Measures of diversity:

Fractionalization is a numerical representation of the number and size of ethnic, linguistic, and/or religious groups in a country.

Other measures look at their relative size (is there one dominant group and a bunch of small groups) or geographic concentration (do different ethnic groups live together or apart).


Greed-based theories focus on the financial incentives to participate in a civil war.  These incentives can be at the micro or macro level. Paul Collier and Anke Hoeffler argue that in poor countries, it is easy to recruit members of armed militias because the money they might earn from conflict is more than what they might earn from farming or other economic activities.  A different “greed” based motivation focuses on the role of natural resources.  Rebels will seek to take possession of valuable resources such as oil and then profit off of them.  The easiest way to think of this is in terms of conflict diamonds.  Trade in diamonds funded the civil war in Sierra Leone, and similar problems are arising with trade in rare minerals (like tantalum) used in modern technology like smart phones, which contributes to conflict in the Democratic Republic of Congo.  In addition, not only did the Islamic State successfully target and operate oil fields in Iraq and Syria, but the Movement for the Emancipation of the Niger Delta has successfully disrupted access to Nigeria’s off-shore oil fields by targeting the trucks shipping easy-to-sell refined products from upstream oil facilities.  Trade does not need to be legal to fund war – the FARC and right-wing paramilitary groups fought intensely for control over coca fields in Colombia’s civil war.


Resource-based theories focus not on why people rebel, but how.  They focus on opportunities to organize against the government. 

For example, James Fearon and David Laitin argue that three factors contribute to civil war: weak governments (which either do not crack down or crack down too hard on insurgents), difficult geography (making it hard to attack rebel groups in mountains, for example), and a large population (providing many people to fight).

There is some overlap between resource-based theories and greed-based theories, in that they both acknowledge that rebel movements require resources to survive.  Resource-based theories define those needs more broadly, however – a “resource” can be petroleum or it could be a social network, a particularly resonant ideology, or a difficult to reach base.  The key is the focus on how rebel movements build support among civilian populations – overcoming coordination problems that would discourage people from getting involved.  This support from the population is what allows one side to win a civil war, according to these views.