The UN has developed a diverse range of peacemaking tools, including different forms of political initiatives (diplomatic, technocratic, and political-development missions) and peacekeeping operations. Yet we know surprisingly little about when and why we observe the onset of different types of UN missions. Examining an “escalatory trajectory,” we analyze the United Nations Peace Initiatives data,

This article examines the conditional effect that repression has on non-violent vs. violent mass mobilization. While governments often resort to violence to deter future mobilization, studies of the repression–dissent nexus have produced divergent evidence with regard to the effect of repression. Many argue that repression tends to backfire, while others demonstrate its effectiveness in reducing mobilization

Existing research shows that education reduces the likelihood of individuals’ participation in political violence and increases conventional political participation, such as voting. However, how does education affect political behavior in authoritarian contexts where opportunities for conventional political participation are limited or non-existent? Focusing on higher education, I argue that college

The province of Aceh in Indonesia provides a promising case for studying the economic legacy effects of conflict given subnational district-level data on violence and gross domestic product. We demonstrate specific negative economic legacy effects of armed conflict despite a general peace dividend: whilst all districts in Aceh grow faster after conflict ends in 2005 than during the conflict, the districts

Quantitative research on arms transfers has not adequately accounted for broader theories of international relations. We review the specialized literature on arms transfers and examine how arms transfers fit with the broad international relations theories. We derive and test seven hypotheses based on realist, liberal and constructivist theories using a dataset of all non-US/Russian aircraft transfers

This article introduces the latest iteration of the most widely used dataset on interstate conflicts, the Militarized Interstate Dispute (MID) 5 dataset. We begin by outlining the data collection process used in the MID5 project. Next, we discuss some of the most challenging cases that we coded and some updates to the coding manual that resulted. Finally, we provide descriptive statistics for the new

The Terrorism in Armed Conflict project integrates the Uppsala Conflict Data Project sample of rebel organizations with START’s Global Terrorism Database, covering 409 organizations for 1970–2013. For many Global Terrorism Database incidents, perpetrator information is missing, or ambiguous. Because the accuracy of perpetrator information likely varies systematically, simply dropping these incidents

In this article, we first formulate some theoretical expectations about the development of the gender gap in voting in post-conflict situations. Second, we test these expectations on five cases, including two civil wars, the Ivorian Civil War (2011) and the Malian Civil War (2013–2015), and three major international Israeli conflicts, the Yom Kippur War (1973) and the First and Second Lebanon Wars

In war-torn countries, elections are held to support peacebuilding, but they sometimes trigger new violence. While peacekeeping operations (PKOs) regularly accompany electoral periods, we lack systematic knowledge on how they influence election-related violence. I argue that variation in peacekeepers’ activities is fundamentally important: only if PKOs assist with securing and organizing elections

How do state-recognized traditional authorities (TAs) influence local-level stability? Policies that recognize and give TAs public authority, particularly in many sub-Saharan African countries, have attracted growing scholarly interest in TAs. Drawing empirical evidence from South Africa, I test a proposition that internally contested TA structures contribute to grievances and opportunities that give

Violent crime in Mexico occurs at a rate that dwarfs the human costs of most contemporary civil wars, and the drug cartels responsible for the violence exercise de facto control over significant geographical territories. In this respect, the Mexican “drug wars” resemble conflicts over the control of rich natural resources in Sub-Saharan Africa and elsewhere, blurring the distinction between “political”

The European Union, the United Nations, and the United States frequently use economic sanctions. This article introduces the EUSANCT Dataset—which amends, merges, and updates some of the most widely used sanctions databases—to trace the evolution of sanctions after the Cold War. The dataset contains case-level and dyadic information on 326 threatened and imposed sanctions by the EU, the UN, and the

Why are there so few female suicide bombers despite their tactical effectiveness? To explain the rarity of this phenomenon, I examine the tradeoffs that armed groups face when using female suicide bombers. While rigid gender norms make female bombers more effective because security personnel are less suspicious of them, gender inequality also drives down the demand for female suicide bombers. I posit

This paper introduces the new dataset of Political Agreements in Internal Conflicts (PAIC) and presents its first application. PAIC captures the institutional provisions in political agreements concluded between 1989 and 2016. It provides information on 91 variables, along five dimensions: power sharing, transitional justice, cultural institutions, territorial self-governance and international assistance

Building upon research that found that coalitions are more likely to win wars, recent work has sought to differentiate effective from ineffective coalitions. Much of this work focuses on characteristics of member states and not the coalition itself. This paper takes a first step in exploring how the structure of a coalition contributes to its performance. Specifically, coalitions vary in how much control

The majority of literature on civil–military relations has focused on coups d’état. Yet, studying lesser forms of military insubordination can offer valuable insight into the true condition of states’ civil–military relations. This paper introduces a data collection effort on mutinies across Africa from 1950 to 2018, revealing several interesting trends. First, most African countries have experienced

We introduce the Freedom of Information Archive (FOIArchive) Database, a collection of over 3 million documents about state diplomacy. Substantively, our database focusses on the USA and provides opportunities to analyze previously classified (or publicly unavailable) corpora of internal government documents which include the raw—often full—text of those documents. We also provide within-country diplomatic

Little is known about how transitions in the government of mediators affect conflict dynamics and resolution. To address this shortcoming, we study executive turnovers of mediators during ongoing interventions in civil war. Mediation effectiveness is largely driven by (trustworthy) information provision and sharing. Changes in mediators’ leaderships have the potential to undermine this, lowering mediation

This paper addresses the relationship between rebel training from external sponsors and civil war outcomes. While past research has examined how foreign support, broadly, shapes the dynamics of civil wars, little attention has been paid to how foreign training of rebel fighters affects civil wars. We theorize that rebels that receive training from formerly successful rebels are more likely to experience

We analyze the sources of two politically relevant, yet opposing emotions: empathy and Schadenfreude. We propose that group and individual-level political factors affect empathy and Schadenfreude toward other groups. Using a survey experiment conducted in Lebanon we find that, when presented with a prompt about political repression, respondents are less likely to express empathy and more likely to

Democracy is one of the most consistent predictors of terrorism. Yet we know little about why there is an apparent relationship between terrorism and democracy. In this article, I argue that previous democratic breakdown is a significant predictor of terrorism. While democratic civil liberties increase the opportunity to carry out terrorist attacks, they do not explain why groups are motivated to use

Social science answers to the essential question of group conflict have focused on two main explanations—their motivating “grievances” and their mobilization “capacity” for collective action. Recent years have seen a renewed focus on grievances in the form of horizontal inequalities (between-group inequality), but the important conceptual and potential empirical differences between horizontal inequality

How do different degrees of displaced people’s hardship shape their expectations of peace and violence in post-conflict societies? We develop a novel explanation and empirically examine it using su...

Why do some international crises escalate into violence while others do not? I argue that an understanding of crisis behavior necessitates awareness of the processes preceding a crisis and propose two mechanisms that link precrisis hostility with crisis violence. The population fatigue mechanism suggests that precrisis hostility interrupts the everyday life of a population, strengthening its demand

Does the public in authoritarian regimes disapprove of their leaders’ backing down from public threats and commitments? Answers to this question provide a critical micro-foundation for the emerging...

How do wartime legacies affect repression after the conflict ends? Irregular forces support the government in many civil wars. We argue that if this link continues after the war, respect for human ...

This research examines the relationship between economic sanctions and income inequality of sanctioned states. Economic sanctions have a discernible effect on target income inequality. I argue that such an effect significantly varies across sanctions instruments and economic conditions of sanctioned countries. Data analysis for 152 countries from 1974 to 2011 shows that import sanctions increase inequality

Violent crime in Colombia is analyzed following the demobilization of ex-combatants using municipal-level data. The main findings are that an increased presence of ex-combatants does not systematic...

In this paper, we study the evolution of accountability in autocracies and the consequent progressive economic and political mismanagement in terms of information changes. It is often held to be tr...

What is the relationship between rebel governance and rebel military strength? Most existing research assumes that rebel governance enhances the military strength of the rebel group. I test this assumption with an original dataset of rebel governance services. The quantitative evidence presents a more complicated picture that belies a straightforward link between the two: governance appears to have

This article introduces the War Terrain Indices and Geospatial Representation Dataset (WARTIGER). This dataset addresses a dearth of quality terrain data in the study of interstate war outcomes. It...

Scholars are increasingly investigating the effectiveness of removing militant groups’ leaders; to date, their findings have been mixed. Rather than seeking consistent evidence, this article explai...

Leaders are incentivized to repress in the face of mobilized dissent. However, leaders are unable to repress alone and rely on repressive agents, who can shirk the order and weaken the leader’s control. I use a formal model to analyze when the leader can use repression strategically to avoid defection, based on leader type. Each type has incentives to repress to distort the leader’s risk of removal

The literature on government violence focuses primarily on the repression of dissent. But not all state violence targets groups who oppose the government. Much of it targets criminal suspects, immigrants, and other marginalized groups who are not perceived to be challenging the government’s authority. The vast majority of findings concerning state violence comes from analyses that do not distinguish

How have rebel communication strategies been shaped by the increasingly social nature of the internet and the constant changes of information and communication technology in a Web 2.0 world? Rebel groups’ ability to disseminate a message has previously been constrained by the size of the audience they could reach through traditional technologies and the costs of those technologies. Emerging social

Most studies examining the effectiveness of international human rights law treat international human rights institutions as equally (un)influential on state behavior. I argue that institutional design explains variation in state response to international human rights law. Using the institutions in the Inter-American Human Rights System (Court and Commission), I argue that judgments from the highly

Under what conditions do religious groups engage in peace activism? Religious groups engage in peace activism if the associated costs are low and they compete with either conflict party over the in...

This special issue is dedicated to Will H. Moore’s enduring influence on peace science research and the community of peace science scholars. The five pieces in this special issue exemplify Will’s dedication to the development of rigorous concepts and theories that generate testable hypotheses about political violence and are evaluated using novel, fine-grained data. Will’s pioneering contributions

Many scholars of contentious politics claim there is no such thing as a group that uses only one tactic, yet scholars, pundits, and the public routinely use single-minded terms like protestors, dissidents, and terrorists. Other scholars and research programs suggest that some groups are specialists who tend to stick to a single tactic to achieve their goals, such as non-violence, violence, or specific

This article introduces the Ethnic One-Sided Violence dataset (EOSV) that provides information on the ethnic identity of civilian victims of direct and deliberate killings by state and non-state actors from 1989 to 2013. The EOSV dataset disaggregates the civilian victims in the one-sided violence dataset from the Uppsala Conflict Data Program by identifying which ethnic group they belong to, using

Whereas protests have been discussed predominantly in terms of collective action issues, achieving coordination does not always guarantee success. Protest groups must also back their demands with s...

How does the oil wealth of a potential target state affect the likelihood of the US public favoring the use of military force? Recent studies suggest that public opinion on foreign policy is responsive to the core characteristics of target states, such as regime type and majority religion. This article advances this research agenda by examining the effects of intra-regime heterogeneity in respect of

This data article reviews the revised “peace data,” describing the motivations behind them and offering a general description of the different peace scale levels—severe rivalry, lesser rivalry, neg...

Persistent brideprice inflation has been linked to greater political violence. However, empirically testing this argument is complicated by the paucity of data on brideprice. We argue that despite ...

Crisis escalation to war is a subject of longstanding interest. Case studies, formal models and statistical analysis offer compelling explanations for why some crises escalate to war while others d...

We introduce a dataset on air power. Air power is the ability to inflict damage on an adversary through the air, and its successful application depends on achieving command of the skies. To achieve command of the skies, countries invest in a variety of types of military hardware and training, especially fighter aircraft. Our dataset contains information on the number, type and technological characteristics—including

Previous research has shown that successful non-violent resistance (NVR) campaigns promote democracy compared with violent revolutions and top-down liberalization. However, research to date has not...

This essay examines the relationship between history and the quantitative study of international conflict. The usual distinction between these two pursuits does not hold up to close scrutiny. In fact, both research communities are in the business of using theory to explain social processes that occur within historical bounds. Making these historical bounds explicit is an appropriate response to the

Do coups affect patterns of political violence like violations of physical integrity rights? Do these patterns vary depending on whether coups succeed or fail? We argue that political uncertainty from coups decreases respect for physical integrity rights. Post-coup regimes preemptively repress as a show of strength to deter threats from those excluded from power and settle scores through cycles of

Trade–conflict studies have shown that economic dependence can promote peace by costly signaling resolve. However, with higher economic integration, targets also become more vulnerable to coercion and potential challengers are incentivized to bluff. In return, target states may resist more, raising the question of whether trade still promotes peace. I theorize that bluffing does not stoke conflict

How do autocracies structure their civil–military relations? We contend that personalist dictators are more strongly associated with counterbalancing than other authoritarian regime types. Personalists are characterized by weak institutions and narrow support bases, a lack of unifying ideologies and informal links to the ruler. They thus have strong incentives to coup-proof and, as we contend, counterbalancing

How does development aid shape democracy after civil conflicts? I argue that political aid conditionalities and the economic utility that recipient elites gain from office give rise to a rent-seeki...

A primary motivation for forming military alliances is to deter adversaries. However, some alliances are more effective at deterrence than others. Deterrence theory suggests that an alliance may fa...

Is there a trend toward the regionalization of peacekeeping? Does regionalization undermine the United Nations (UN) system of collective security? To answer these questions, we present an innovative dataset of peace operations. Covering the 1947–2016 period, the dataset captures every UN and non-UN peace operation, information on mission type, the existence of target state consent and UN authorization

How does demographic inclusion in domestic security institutions affect security provision in divided societies? Police officers rely on information from citizens to identify problems and allocate resources efficiently. Where conflict along identity lines erodes trust between citizens and the state, the police face difficulty obtaining information, hindering their ability to provide public safety.

Which third parties are more likely to manage interstate conflicts? Once they do, what kind of conflict management methods do they use? I argue that ethnic, language, and/or religious ties between a potential third party and disputant states can affect both the likelihood and the type of conflict management. If there are strong identity ties (ethnic, language, and/or religious) between the majority

Why are some locations more attractive targets for transnational terrorism than others? Remarkably little is known about the local-level conditions and attributes that determine precisely where transnational terror attacks occur within targeted countries. To date, quantitative terrorism research identifies country- or region-level correlates of terrorism, neglecting possible local factors. In this

There is a growing consensus that repression and counter-insurgency can be effective when selective. Yet the empirical evidence is mixed and theories specify that (unmeasured) perceptions of target selection matter. This article addresses this gap by directly measuring individuals’ interpretations of a coercive policy which varies in target selection. It employs original surveys with Palestinians on

I contend that a state’s position in the global trade network affects the initiation and outcome of sanction threats. A state is vulnerable, and thus more likely to acquiesce, when its trade has low value to trade partners that are well connected to the global trade network. Conversely, a state has leverage that could motivate the use of sanction threats when its trade has high value to trade partners

This study uses a visualization technique, systemism, to integrate ICB Project findings about crisis, escalation and war in particular. The domain of the analysis, 1999–2017, is the period following the authoritative review of research in Michael Brecher (1999; International studies in the twentieth century and beyond: Flawed dichotomies, syntheses, cumulation, International Studies Quarterly 43: 213–264)