Civil war

A civil war is a form of high-intensity armed conflict fought between organised groups within the same sovereign state. Such conflicts typically arise when factions seek to seize control of national government, demand autonomy or independence for a particular region, or attempt to force significant political or policy reform. Civil wars are among the most destructive forms of intrastate conflict, often involving regular armed forces, prolonged violence and extensive societal disruption.

Definitions and Conceptual Frameworks

The term civil war is derived from a Latin expression used to describe internal conflicts in the Roman Republic. Modern scholarship offers several definitions, reflecting the complexity and variability of civil conflicts. James Fearon identifies civil war as organised and sustained violence within a state, perpetrated by groups striving for control at the centre or within a specific region. Ann Hironaka further specifies that one of the warring parties must be the state polity. Stathis Kalyvas emphasises that the combat occurs within the borders of a recognised sovereign entity and involves parties that were subject to a common authority at the onset of hostilities.
A central point of debate concerns the threshold at which internal unrest qualifies as civil war. Some scholars stipulate a minimum of 1,000 total casualties, with at least 100 from each side, while the widely used Correlates of War dataset classifies a civil war as producing over 1,000 battle-related deaths per year. Such criteria exclude several notable lower-intensity struggles but reflect attempts at standardised classification for comparative research.

Historical Patterns and Trends

Civil wars have occurred throughout history, but their frequency and duration have varied markedly. The period 1900–1944 saw relatively short conflicts, averaging approximately eighteen months in duration. Since the end of the Second World War, civil wars have lasted significantly longer, averaging more than four years. This trend has increased the number of ongoing conflicts at any given time; whereas fewer than five concurrent civil wars existed before 1950, more than twenty were underway towards the end of the Cold War.
Post-1945 civil conflicts have had devastating consequences, causing more than twenty-five million deaths and the forced displacement of millions. Countries such as Somalia, Myanmar, Uganda and Angola witnessed severe economic decline after becoming embroiled in prolonged internal conflict, despite previously promising economic or political trajectories.

International Dimensions and Intervention

Most modern civil wars involve foreign powers to some extent, whether through direct military support, diplomatic involvement, or covert assistance. Patrick M. Regan’s analysis of intrastate conflicts between the end of the Second World War and 2000 demonstrates that roughly two-thirds experienced some form of international intervention. Such involvement can prolong conflicts, shift power balances or increase humanitarian costs.

Criteria for Legal Recognition and the Geneva Conventions

Although the Geneva Conventions do not explicitly define the term civil war, they outline legal expectations for parties involved in non-international armed conflicts. Under the guidance of the International Committee of the Red Cross (ICRC), additional interpretive criteria have been proposed to aid in identifying when internal violence warrants recognition as a civil war for the purposes of humanitarian law.
These conditions broadly address factors such as the existence of an organised insurgent force, the ability of both sides to observe the laws of war, the extent of territorial control, and whether the conflict has been acknowledged by the legitimate government or by international bodies such as the United Nations Security Council or General Assembly. While these guidelines provide structure, the ICRC cautions that they should not be applied as rigid prerequisites.

Causes of Civil Wars

Research identifies three prominent categories of explanations for the onset of civil wars: greed, grievance and opportunity.

1. Greed-based explanations argue that conflicts arise when groups perceive opportunities for economic gain. This view posits that access to valuable commodities or exploitable resources can motivate organised rebellion.
2. Grievance-based explanations focus on social, ethnic, religious or political injustices. Discrimination, exclusion, inequality or state repression may produce collective discontent strong enough to inspire violent resistance.
3. Opportunity-based explanations, considered by many scholars to be the most influential, examine structural conditions that make rebellion feasible. James Fearon and David Laitin emphasise factors such as weak state capacity, difficult terrain, large populations and limited policing capabilities, which lower the cost of insurgency and raise the likelihood of internal conflict.

Economic and Structural Determinants

Major empirical work on civil war causation includes the Collier–Hoeffler Model, which analysed conflict data from 1960 to 1999. This framework identified several significant predictors of civil war, including:

• Dependence on primary commodity exports, which increases the risk of conflict due to the ease of extortion or capture of resources such as oil or minerals. A state with high reliance on such commodities may face a markedly greater chance of internal conflict than one with a diversified economy.
• Financial support from national diasporas, which can dramatically increase the likelihood of rebellion by providing external funding, weapons or advocacy.
• Levels of education and income, where higher male secondary-school enrolment and greater per-capita income reduce the probability of conflict by strengthening state capacity and limiting recruitment opportunities for rebel groups.

These findings collectively demonstrate that civil wars are shaped not only by identity-based divisions but also by broader socio-economic and political environments.

Consequences and Long-Term Effects

Civil wars frequently lead to extensive human suffering and societal disruption. High casualty rates, population displacement, destruction of infrastructure and breakdown of governance are common. Prolonged conflict can precipitate economic collapse, weaken social cohesion and hinder post-war reconstruction for generations.
Beyond immediate devastation, civil wars expand regional instability, encourage proliferation of small arms, and create conditions conducive to disease outbreaks, famine and the entrenchment of war economies. Recovery is often slow, requiring sustained peacebuilding, institutional reform and international support.