top of page


Peer Reviewed Publications

9) "Recruiting Rebels: Introducing the Rebel Appeals and Incentives Dataset." Accepted and Forthcoming.   Journal of Conflict Resolution.

Link to Article

Link to Replication Materials

8) Karstens, Mikaela, Michael J. Soules, and Nicholas Dietrich 2023. “A Crack in the Foundation: Event Data, Newspaper Databases, and Threats to Validity and Replicability.”  PS: Political Science and Politics

Link to Article 

7) "Thinking Outside of the Box: Transnational Terrorism in Civil Wars." Accepted and ForthcomingInternational Studies Quarterly.

Link to Article

Link to Replication Materials 

6) Soules, Michael J. 2022. “The Tradeoffs of Using Female Suicide Bombers.” Conflict Management and Peace Science 39 (1): 3-23.

Link to Article

Link to Replication Materials 

5) Soules, Michael J. 2022 “Martyr or Mystery? Female Suicide Bombers and Information Availability.” Studies in Conflict and Terrorism 45 (1): 62-91.

Link to Article 

Link to Replication Materials 

4) Avdan, Nazli, James A. Piazza, and Michael J. Soules,. “Silver Lining? The Effects of Epidemics on Terrorist Groups.” Accepted and Forthcoming. Terrorism and Political Violence

Link to Article

Link to Replication Materials 

3) Palmer, Glenn, Roseanne McManus, Vito D’Orazio, Michael R. Kenwick, Mikaela Karstens, Chase Bloch, Nicholas Dietrich, Kayla Khan, Kellan Ritter, and Michael J. Soules. “The MID 5 Dataset, 2011-2014: Procedures, Coding Rules, and Description. Conflict Management and Peace Science 39 (4): 470-482.

Link to MID Project Website

2) Piazza, James A. and Michael J. Soules. 2021. “Terror After the Caliphate: The Effect of ISIS Loss of Control over Population Centers on Patterns of Global Terrorism.” Security Studies 30 (1): 107-135.

Link to Article

Link to Replication Materials 

1) Soules, Michael J. 2020. “Women in Uniform: The Opening of Combat Roles to Women in State Militaries.” International Interactions 46 (6): 847-871.

Link to Article

Link to Replication Materials 

Working Papers

5) "Fighting to the Bitter End: Rebel Recruitment Tactics and Civil War Outcomes" Job Market Paper.

Abstract: How do recruitment tactics affect the longevity and success of rebel groups in civil wars? The conventional wisdom holds that recruitment strategies relying more on ideological appeals, relative to material incentives, will attract more committed recruits who are more invested in the success of their groups than their materially motivated counterparts. However, I argue that highly committed recruits provide rebel organizations with a double-edged sword, as the most devoted militants will be less willing to compromise with governments and can spark internal clashes over ideological issues. From this standpoint, the effects of recruitment practices on the fate of rebel organizations are unclear. To add clarity to this debate, I introduce novel data on the persuasive recruitment practices of  rebel groups that operated between 1989 and 2011. I find that while groups that rely more on ideological appeals than material incentives for recruitment survive longer, they are not more likely to achieve their goals. This paper makes an important theoretical contribution by highlighting the drawbacks of ideologically based recruitment strategies and an empirical contribution by introducing novel data on rebel recruitment tactics.

Link to Manuscript

4) "Convincing Them to Fight: How Rebel Groups Choose Their Recruitment Tactics." Under Review.

Abstract: Why do some rebel groups rely heavily on material incentives for recruitment, while others depend more on ideological appeals? Much of the literature tends to focus on differences in the recruitment tactics between “resource rich” and “resource poor” rebels. In this research note, I investigate how the material and ideological resources available to rebel groups, and their long-term goals, shape their recruitment strategies. I seek to expand our theoretical understanding of rebel recruitment by examining the effects of different types of material resources, not just the presence of absence of such wealth. However, I argue that groups also have agency in formulating their recruitment strategies and that such choices are not based entirely on available economic and social resources. Specifically, I analyze how militants’ long-term goals affect their recruitment. Using novel data on the persuasive recruitment strategies of over 220 rebel groups active across the world, I find strong evidence that groups that exploit a greater breadth of natural resources are more likely to recruit with material incentives. However, I find that while lootable resources affect recruitment patterns, non-lootable resources do not. Surprisingly, I do not find clear evidence that existing ethnic and religious ties help facilitate ideological-based recruitment. Finally, the results indicate that rebel movements with secessionist aims are more likely to rely on ideological-based recruitment strategies. Thus, this note uses novel data to provide nuance to our understanding of how material and social resources affect the recruitment strategies of rebel organizations.

3) Howarth, Kathryn and Michael J. Soules. "Rebel Recruitment and Terrorism in Civil War." Under Review.

Abstract: How does forced recruitment affect rebel groups’ use of terrorism in civil wars? Prior scholarship finds that forced recruitment is associated with a variety of types of violence against civilians. However, previous quantitative work has not considered how forced recruitment affects the various types of violent strategies rebels can adopt. We argue that groups employing forced recruitment will launch a greater number of attacks against both soft and hard targets. The former facilitates the formation of bonds among abducted recruits, while the latter are more dangerous operations that groups are more willing to sacrifice abducted recruits for. However, we expect that such groups will come to rely more on soft target, relative to hard target, attacks because soft target attacks are less logistically complex and costly, which abducted recruits are better suited for. Using data on the terrorist attack strategies of all rebel-dyads present in the Uppsala Conflict Data Project (UCDP) Dyadic Dataset between 1970 and 2013, we find robust evidence that groups employing forced recruitment devote more resources to launching a greater number and percentage of their attacks against soft targets. We find more modest evidence of a link between forced recruitment and hard target attacks.

2) Rebel Group Heterogeneity and Sexual Violence.

Abstract: What role does ethnic identity and mobilization play in explaining the prevalence of sexual violence during civil war? Previous scholarship remains divided on this issue. In this paper, I investigate how the ethnic composition of rebel movements shapes their use of such forms of violence. Drawing on existing literature, I argue that multi-ethnic rebel organizations are more likely to suffer lower levels of cohesion and greater command-and-control problems, both of which increase the probability of rebels perpetrating acts of sexual violence. Using existing data on the ethnic composition of rebel groups and their use of sexual violence, I find support for the notion that multi-ethnic militant movements are more likely to engage in sexual violence. However, when I empirically probe this relationship further, I do not find evidence supporting the command-and-control mechanism, suggesting that ethnic fractionalization within rebel groups might drive the increased use of sexual violence because of efforts by such groups to increase internal cohesion.

1) Avdan, Nazli, Michael J. Soules, and James A. Piazza. “Targeting the Vulnerable: Internally Displaced Populations and Sexual Violence in Civil Wars.”

Abstract: Scholars and policy commentators frequently note the vulnerability of internally displaced populations (IDPs), including populations displaced by civil war, to sexual violence. However, while some rebel groups in civil wars exploit such vulnerabilities with widespread perpetration of sexual violence, many do not. What factors drive armed groups to abuse such populations? We argue that groups with secessionist aims are less likely to commit sexual violence against IDPs. As scholars have posited, secessionist organizations engage in legitimacy seeking behavior because they need both domestic and international actors to support their claims of sovereignty. Thus, they will avoid exploiting vulnerable populations, particularly those that receive significant international attention, such as IDPs, because they have greater incentive to appear legitimate. Using data on all rebel groups included in the Uppsala Conflict Data Program’s Armed Conflict Database from 1990 – 2008, we find support for our hypotheses. Specifically, we produce evidence that while the presence of IDPs increases the probability that rebels perpetrate sexual violence, secessionist goals significantly reduce these effects.

Works in Progress


"State Security Forces and Counterterrorism." 

“Rebel Competition and Forced Recruitment.”

Kahn, Kayla, James A. Piazza, and Michael J. Soules. “The Electoral Performance of Far-Right Populist Political Parties and the Prevalence of Right-Wing and Left-Wing terrorism.”

“Female and Male Right-Wing Extremists in the United States.”

“Gender Norms and Support for Political Violence.”

"Far From Home: Transnational Terrorism and Civil War Outcomes"

Brandon Bolte and Michael J. Soules. “Comparing the ISIS and al-Qaeda Networks” 

bottom of page