Inequality and political violence: A review of the literature

The author examines the 'quantitative-qualitative mismatch' in conflict studies, where large-N statistical analyses often find no link between income inequality and violence, while case studies suggest a strong connection. The paper posits that political violence is a group phenomenon and therefore driven by horizontal inequalities (HIs)—systematic disparities between ethnic, religious, or regional groups—rather than vertical inequalities (VI) between individuals. The author proposes a theoretical framework where HIs create both motives (grievances) and opportunities (resources and cohesion) for mobilization. The review concludes that while measuring HIs is challenging, evidence from survey-based data and disaggregated studies supports the link between HIs and various forms of political violence, including civil war and urban disorder.

• Quantitative studies focusing on vertical inequality (VI)—the distribution of income or land among individuals—have generally failed to find a statistically significant relationship between inequality and political violence.
• The author argues that the failure of statistical studies to find a link is a conceptual flaw, as political violence is a group-based phenomenon requiring a focus on horizontal inequalities (HIs), which are systematic disparities between ethnic, religious, or regional groups.
• Horizontal inequalities are multidimensional, encompassing not only economic factors like income but also social and political dimensions.
• HIs can spur collective action through two primary mechanisms: grievances (motives) and opportunities. Grievances can arise from both relative deprivation among the poor and fear of redistribution among the relatively privileged.
• Socioeconomic HIs provide internal opportunities for mobilization; richer groups possess more material resources to sustain a rebellion, while disadvantaged groups have lower opportunity costs for recruits and stronger grievances.
• Evidence from qualitative case studies and some quantitative disaggregated studies suggests that HIs are associated with a range of violence, from racial riots in Malaysia to civil wars in Uganda, Côte d’Ivoire, and Sri Lanka.
• The author identifies a significant data quality issue with the G-Econ dataset, noting that for most of Africa and parts of Asia (such as Indonesia), the data is of 'low quality' or 'some regional data', making it less reliable than Demographic and Health Surveys (DHS) for measuring HIs in developing countries.
• HIs are hypothesized to be more relevant for the onset of conflict and for politically motivated violence (such as secessionist or ethnic conflicts) than for routine violence or non-political crime.
• Horizontal inequalities are likely to be more visible and pronounced in urban areas due to the presence of migrants and born city dwellers, increasing the risk of urban social disorder.

APA

Østby, G. (n.d.). Inequality and political violence: A review of the literature. Peace Research Institute Oslo. https://cdn.cloud.prio.org/files/3941f8ab-d30d-4759-b7b7-9eccd5be16c7/Inequality and political violence A review of the literature.pdf?inline=true

Chicago

Østby, Gudrun. Inequality and political violence: A review of the literature. Peace Research Institute Oslo, n.d. https://cdn.cloud.prio.org/files/3941f8ab-d30d-4759-b7b7-9eccd5be16c7/Inequality and political violence A review of the literature.pdf?inline=true.

Wikipedia

{{cite report |last1=Østby |first1=Gudrun |title=Inequality and political violence: A review of the literature |publisher=Peace Research Institute Oslo |url=https://cdn.cloud.prio.org/files/3941f8ab-d30d-4759-b7b7-9eccd5be16c7/Inequality and political violence A review of the literature.pdf?inline=true |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{stbyndinequality, author = {Østby, Gudrun}, title = {{Inequality and political violence: A review of the literature}}, institution = {Peace Research Institute Oslo}, url = {https://cdn.cloud.prio.org/files/3941f8ab-d30d-4759-b7b7-9eccd5be16c7/Inequality and political violence A review of the literature.pdf?inline=true}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }