Abstract
Recent research on Islamist radicalization has directed greater attention to the conjunctions of causes and staged processes that draw individuals into violent extremism. Yet research is still grappling with the varying extents of individual action and external factors, including social networks, peer pressure, propaganda, cultural and socio-economic conditions, on radicalization processes. At bottom, this investigation revolves around the context in which individuals live and the influences acting upon them. Identifying patterns of these conditions is essential to understanding how individuals come to engage in violent extremism. This article presents a configurational analysis of foreign fighters that travelled to fight in the Syrian War. The paper presents data gathered from interviews, security and judicial records, and secondary sources on individuals from the Western Balkans (predominantly Bosnia and Herzegovina) that joined Islamist groups in the Syrian War. Individuals’ relationship with longstanding Balkan radical milieus and with key Islamist preachers were coded. Using qualitative comparative analysis (QCA) techniques, we present a systematic description of characteristics of foreign fighters.
Amid grappling in European states with the issue of returning foreign terrorist fighters, radicalization and engagement in violent extremism remain worrying and also puzzling processes for researchers, security experts, police, and intelligence professionals. More than 1000 people from the Balkan region travelled to Iraq and Syria between 2012 and 2016 to join Islamist groups, including the Islamic State (IS) and Al-Nusra Front (JN).Footnote1 The question of why these individuals engaged in violent extremism involves complex causes and multiple pathways. Featuring prominently among the causes are social influences, whether from family, peers and recruiters, or radical imams. This article identifies patterns of interpersonal and community influences among a subset of fighters that travelled to Syria.
The phenomenon of foreign fighters, “non-citizens of a state experiencing civil conflict who arrive from an external state to join an insurgency,”Footnote2 is not new, especially among militant Islamism. Individuals or small groups joined the cause of jihad in several previous conflicts, including Afghanistan, Chechnya, Bosnia, Somalia, and Iraq. Yet the recurrence and evolution of processes of radicalization and engagement in violent extremism demand continuous research on foreign fighters. In 2015, during the influx of foreign fighters to Syria, Nesser argued that “the only consistent feature of terrorist cells is that no cells have formed in the absence of entrepreneurs.”Footnote3 This argument points to the importance of influential local figures who play a role in the radicalization of Islamists and propel them to become foreign fighters. Inspired by this finding, which appears in myriad radicalization studies,Footnote4 this article presumes that foreign fighters are influenced by authority figures in their immediate social environment without necessarily being directed by them.
This article examines the cases of Balkan (predominantly Bosnian) foreign fighters and their families. The question why the Balkans produced a comparatively high number of foreign fighters has several plausible answers: political and national contextual conditions, war legacies, pre-existing radical networks and leadership, and various group and individual grievances. Notwithstanding these factors, the emergence of a radical milieu in response to postwar fragility was crucial for the mobilization of Balkan foreign fighters.Footnote5 Jihadists from the Balkans, especially from areas of fighting in the 1990s, have more and better opportunities to socialise in local Salafi milieus, which have come to occupy a prominent social role in many places, filling voids of order and redefining post-conflict social relations.
Our analysis investigates individuals’ relationship with the radical milieu in the Balkans before travelling to Syria. It seeks to answer the following research questions: Were foreign fighters tied to radical influencers and social circles before travelling to the battlefield? If yes, what patterns of social connections can be identified surrounding their decision to engage in violent extremism (i.e. by travelling to Syria)? Answering these questions, ideally across numerous cases, helps us understand how individuals radicalize and ultimately engage in violent extremism.
The study builds on previous research on Islamist radicalization in the Balkans.Footnote6 We present data gathered through fieldwork in the Balkans in 2018 and 2019, including interviews, material from security and judicial records, and media reports on individuals from the region that became foreign fighters in the Syrian War. To analyze the data, we coded the existence of individuals’ relationship with the Bosnian radical milieu and with prominent Islamist influencers. We applied qualitative comparative analysis (QCA) techniquesFootnote7 and thereby present a systematic description of characteristics that, we argue, matter to the recruitment of Balkan foreign fighters.Footnote8
Our findings refer to patterns of social interaction of fighters preceding their departure to Syria. Foremost among these findings is confirmation of the equifinality of extremist engagement: some fighters are spurred on by radical influencers, including preachers and recruiters; others are primarily influenced by peer-to-peer radicalization. Radical influencers in some cases are part of the family being radicalized; in others, they facilitate the radicalization of like-minded peers in the broader milieu where multiple sources of influence play a role. We consider these multiple sources of influence in our QCA and post-QCA discussion of cases. We underscore the importance of analyzing foreign fighters not only as individual actors, but also as part of a group phenomenon, with boundaries that are determined by pre-existing social relations. In this way we contribute to the literature on radicalization within the broader scholarship on terrorism.
Radicalization and Violent Extremist Engagement, and the Roles of Preachers and Radical Milieu Socialization
Recent research on Islamist mobilization in Europe deals with the recruitment of IS foreign fighters and builds on previous research on al-Qaeda networks, home-grown radicalization, and the recruitment of jihadists in the West.Footnote9 The highly decentralized nature of IS foreign fighter recruitment has brought balance to previous debates about whether Islamist terrorism is a top-downFootnote10 or a bottom-upFootnote11 type of threat. It is both. The recruitment of IS foreign fighters demonstrated the top-down constructed propaganda campaigns, whereas bottom-up networks, online groups, and self-recruitment became avenues by which individuals were drawn into terrorism. Nesser stresses the role of so-called “entrepreneurs,” or (as we refer to them in this article) radical influencers, who build cells and provide them with a rationale and purpose; they come from diverse backgrounds, but “are generally committed, charismatic activists with a talent for manipulating people.”Footnote12 Newer studies on radicalization support the argument that it is not only propaganda messages that matter but “the reputation of the messenger themselves.”Footnote13
Radicalization and engagement in violent extremism are relational processes produced by social interaction, social networks, trust, and loyalty-based relationships. Theories of radicalization strongly emphasize the importance of social ties and group dynamics.Footnote14 Such theories have been influenced by research on recruitment processes and participation in social movements.Footnote15 In the West, European foreign fighters had relatively easy access to existing radical networks and thus high numbers of recruits originated there; by contrast, U.S. foreign fighters had less access and were less connected to the conflicts in the Middle East.Footnote16
Previous research on Islamist networks in Europe shows that European jihadists are often recruited through their immediate social environment, including friends and relatives.Footnote17 Thus, there are observable social patterns showing the importance of social networks in engaging in violent extremism. Kinship and friendship bonds play a role in radicalization, as the exposure to ideological content often happens through informal social interaction. People that join the cause of jihad in small groups are often part of social networks with other prospective Islamist militants.Footnote18
Radical Influencers
To conceptualise social patterns that emerge from various social interactions, the paper refers adopts the concept of “radical influencers” inspired by previous research on charismatic authority in Islamist radicalism and militancy. A charismatic leader assumes power and credibility from the “consent” of followers and thus, build a charismatic image and narratives that resonate with a particular audience.Footnote19 Charismatic authority situated in the grassroots radical milieus of the Islamist movement is not necessarily a part of a hierarchical organisation. It may even lack ties to central leadership of a terror organisation. Nevertheless, radical influencers have the power to organise and mobilise an ideologically loyal base; their influence is understood here as a function of their charisma.
Although foreign fighter mobilization is a global phenomenon, case studies on European foreign fighters show that they were often recruited through local communities and small social networks.Footnote20 Individuals have various sets of social relations which may motivate their decision to become foreign fighters. For example, Neumann argues, some individuals became foreign fighters “not because of political events or because they themselves have looked for an opportunity, but because their leader has decided it.”Footnote21 In other words, their motivation is social, driven by religious and political feelings within the radical milieu and manipulated by radical influencers. While radical influencers may be involved in logistical aspects of recruitment and engagement in violent extremism, the essence of their role is to serve as ideological hubs in networks, exercising the greatest influence through framing discourse.
Radical imams perform several key functions in radicalization processes. Neumann and Rogers identify the four most importantFootnote22: first, they serve as key propagandists, who make the basic narrative of Islamist militancy relevant to their followers. Second, they are seen as religious authorities, who provide rulings and justifications for violent jihad. Third, they are recruitment magnets, who attract followers from various backgrounds and integrate them into a coherent network. Fourth, they generate “networks of networks” at national, regional, and international levels by linking different groups and networks. Building on these insights, the article distinguishes between four functions that influencers may perform in relation to foreign fighter recruitment (). These functions typify the role of authority figures in mobilizing people into Islamist militancy.
Table 1. Functions of radical influencers.
Postwar Radical Milieus
The histories of local radical milieus—here understood as conducive environments for radicalization, recruitment, and eventual engagement in violent extremismFootnote23—are important when analyzing how individuals are recruited from European Muslim populations.Footnote24 A radical milieu is not a community built to create extremists but describes the broader community from which extremists rise.Footnote25 Although the networks of Islamist militants often cross boundaries and create similar recruitment patterns, there are distinctions that result from the diverse nature of European Muslim communities. For instance, the histories of the radical milieus across Belgium or Sweden differ from those in Bosnia and Herzegovina or Kosovo. The first two have been shaped by immigration processes; the latter, by war. There are surely commonalities between post-conflict and non-post-conflict fighters, both in their individual profiles and manner of recruitment. Not least among these commonalities are the roles of influencers and localized radical milieus.
The history of the Bosnian radical milieu is not the focus of the paper, but we argue that this social environment matters to what social influences foreign fighters were exposed to before going to Syria. It is therefore worth mentioning three factors that shaped the Bosnian radical milieu in the postwar period. First, several hundred foreign mujahideen fighters participated in different stages of the Yugoslav wars. Their movements spread radical values and set patterns that were solidified in the postwar radical milieu. Second, humanitarian Islamic NGOs became organizational hubs for propagating extreme forms of Islam, especially Salafism. Third, a generation of Bosnian students graduated from Islamic studies programs in Arab countries and, upon their return to the Balkans, actively spread Salafist ideas. Bosnia’s radical milieu emerged amid processes of postwar transformation in which sources of authority and societal norms were being redefined. Together, the model of veteran fighters, Islamic NGOs, and young proponents, all advocating Salafism, provided an answer to the postwar challenges of poverty and social atomization. In promoting that ideology, radical influencers and their followers challenged extant norms and values without always promoting or using violence.Footnote26
Yet Balkan foreign fighters did not radicalize and travel to Syria solely due to the war experiences of their communities and the radical milieus they host. In fact, some foreign fighters left from locations that were untouched by the 1990s wars. What mattered to the recruitment of fighters to Syria was the role of local radical influencers who could influence not only communities exposed to the war and postwar Salafi interventions, but also new followers. Their efforts over time made particular social, religious, and political narratives more accessible and acceptable to larger communities in the region.
Data
This paper stems from a broader project on Islamist radicalization in the Balkans. It gathered data on foreign fighters (and accompanying family members) who travelled from the Balkans to Syria, step one in the research process summarized in . More than 1000 individuals from the region travelled to Syria and Iraq between 2012 and 2016. The Balkan foreign fighter contingent consisted of men, women, and children from Bosnia and Herzegovina (BiH), Serbia, and Montenegro as well as from Bosnian diaspora communities across Europe, the United States, and Australia. The available data shows that more than 400 people of Bosnian descent traveled to Syria with the intention of joining extremist groups such as JN or IS. About a third of them died; some have returned or were captured; others were charged with recruitment-related activities.
Figure 1. Summary of research process.
Since the project’s principal object was investigating the link between longstanding radical milieus, particularly those rooted in the Yugoslav wars, and contemporary Islamist fighters, data collection concentrated most heavily on BiH. Of the 268 cases included in the dataset fully 215 are from BiH. However, the project adopted a blanketing strategyFootnote27 that gathered data on individuals connected to Islamist radicalism in BiH even if residing elsewhere; specifically, other origins of fighters and companions in the dataset include Serbia (11 individuals), Montenegro (14 individuals), and diaspora communities in Western Europe (28 individuals). Data were gathered from interviews, security and judicial records, and secondary sources such as news reporting.
The project included coding of several attributes for each individual (see Appendix A). Most importantly, the project included two key categorical variables: connection to Islamist influencers and relationship with the radical milieu. The first focused on whether there was evidence for an individual connection to radical Islamist influencers that encouraged their followers to become foreign fighters. Prominent among these were Nusret I., whose followers clustered around the commune of Gornja Maoča but also included many individuals engaged online, and Bilal B., whose followers are most closely associated with the commune of Ošve. Our data includes a large swathe of individuals who were clearly influenced by Nusret I. or Bilal B., thus offering an opportunity to assess their role in foreign fighters’ radicalization and engagement in violent extremism.
The second key variable, “relationship with the radical milieu,” refers to how, if at all, individuals are connected to the radical milieu before becoming foreign fighters, in either passive or active positive relationships. Data for this category derives from studying foreign fighters’ biographies and identifying social activities in which they participated. We consider people with a positive active relationship with the radical milieu to be those who actively identify with a cause, community, or group, as evidenced by their activities. Others experience passive exposure to radical subcultures and narratives. Following this logic, people exposed to radical rhetoric through kinship ties have a positive passive relationship with the radical milieu. In some cases, we find no evidence of any relationship with the radical milieu. Such individuals may not have been exposed to socialization in the radical milieu but instead acted upon radical views shaped in their immediate family environment.Footnote28,Footnote29
Our two key variablesFootnote30 along with individuals’ biographical data offer insight into social patterns underlying engagement in violent extremism. displays the categorical values coded in these variables, through which we group cases systematically with QCA techniques.
Table 2. Data table, as calibrated and analyzed in the mvQCA.
Several challenges were encountered in the process of preparing and conducting this data collection. As the research population includes extended Salafi communities that have been marginalized and generally “hidden,” the fieldwork relied on gatekeepers and a personally established network on the ground. Using snowball sample methodology, both formal and informal efforts to access interviewees were made, including contacting prison services and the prosecutors and defenders of individuals sentenced for joining terrorist groups. In some cases, these efforts were unsuccessful for legal reasons, time constraints, or rejection by potential interviewees. Data from secondary sources helps to minimize this shortfall.
Methodology
We apply qualitative comparative analysis (QCA)Footnote31 techniques to group and compare our cases (i.e. individuals who travelled to join jihadist movements in Syria) systematically and thereby detect patterns of violent extremist engagement. Copious research has shown that radicalization and engaging in violent extremism are complex causal processes, marked by conjunctural causation (i.e. caused by the co-occurrence of conditions), equifinality (i.e. multiple sufficient “paths” to radicalization and engagement) and asymmetry (i.e. the explanation for non-radicalization and non-engagement is not the mere inverse of the explanation for radicalization and engagement). These causal features recommend QCA, which for our purposes is useful to create empirical groups.Footnote32
We applied the variant of multi-value QCA (mvQCA) to detect patterns in our data.Footnote33 This variant allows us to incorporate multi-value (or categorical) conditions. summarizes the set values for the mvQCA.
Travelling to the Syrian conflict zone is coded as engagement in violent extremism.Footnote34 However, as our data includes only individuals who did in fact travel to Syria, QCA techniques alone do not empower us to move toward causal inference. Yet by sussing out the most prominent configurations of conditions among our cases we provide an accurate description of the most common patterns of extremist engagement, which we take further by going back to cases: looking at examples of the most prominent patterns, we specify processes and mechanisms at work. Thus, as in , our approach is composed of two complementary techniques. QCA helps to identify cross-case patterns; close inspection of individual and clusters of cases unpacks the processes underlying those patterns.
Finally, a note about case selection and population deserves mention. While contextual (i.e. macro-level) features differ between post-conflict societies, like the Balkans, and non-post-conflict societies, similarities span this divide at the micro-level of individual processes of radicalization and engagement in violent extremism. Post-conflict societies often harbor large radical milieus, and are perhaps more susceptible to radical influencers,Footnote35 but similar socialization dynamics can be observed in a variety of contexts. The difference is in degree, not in kind. Thus, this study provides insights into the role of influencers in structuring the radical milieu and driving engagement in violent extremism.Footnote36
Analysis
Our mvQCA starts with the logical minimization of our data. Logical minimization here denotes the process of systematically summarizing information in the data by revealing set relations. Typically in QCA studies, this produces a solution formula that offers some basis for causal inference. For our purposes, it is merely the “configurations” or groupings of cases that are of interest. displays the output of logically minimizing the data.Footnote37 (QCA studies typically report the truth table, but it is not of much use here, so we report it only in Appendix B.) We are interested in the coverage of these groupings, how many cases are described by the combination of conditions, both how many overall are described (“cases covered”) and how many are only described by a particular grouping (“cases uniquely covered”).Footnote38
Table 3. Unabridged solution table for mvQCA.
The first thing to note is that the multi-value approach helps us to compare the different origins of individuals engaging in violent extremism. shows the shape of set relations across the four origins of our dataset of individuals that travelled to Syria. While acknowledging the different scale of data collection for different countries—again, the project focused on cases from Bosnia and Herzegovina—commonalities emerge across regions. The influence of Nusret I. and Bilal B., for instance, is not restricted to the territory of BiH. A handful of individuals in neighboring countries were connected to these influencers, which distinguishes them from smaller, localized hubs of radical influence.
Figure 2. Set relations from different origins of fighters, Islamic State (is) affiliation, connections to Nusret I. and Bilal B., and positive active (POSACT) relationship to the radical milieu.
visualizes the clustering of characteristics based on individuals’ connection to radical influencers, their relationship to the radical milieu, their role in the conflict, and their group affiliation. The largest cluster, the plurality of foreign fighters, had a positive active relationship with the radical milieu but apparently no connection to the major radical influencers. These cases speak to the importance of immediate social contacts, from family and peers, for engaging in violent extremism. Yet the connection of nearly 40% of individuals to either Nusret I. or Bilal B. reflects the extensive reach and impact of radical influencers.
Figure 3. A Heatmap showing the clustering of cases based on their connection (if any) to radical influencers and their relationship with the radical milieu. Bars within the cells show the proportions of fighters, women, children, and recruiters.
We identify a constellation of recruiters (i.e. rows 17, 38, 39, 40, 46, and 47 in , shaded in dark grey), intermediaries between radical preachers and foreign fighters. Compared to radical preachers, recruiters have less charismatic appeal and far-reaching popularity; but they are still well connected, so they are more active at an operational rather than an ideological level. Some of them travelled to the battlefield themselves and became commanders in the ranks of IS. These individuals were actively involved in the logistical aspects of the recruitment, such as selecting recruits, organizing their travel to and reception in Syria. One of them was considered the “right hand” of Bilal B. This individual, from Bosnia, resided in Austria before going to Syria himself. He died in 2016. In another case, an individual who acted as an imam in a small town in Serbia did not have the fame of a prominent ideologue but was sentenced for recruitment and for joining the IS himself.
Localized Recruitment and Relating to the Radical Milieu
Most conspicuous is the importance of a positive active relationship with the radical milieu. shows that two-thirds belong to this category. displays the majority of cases in each context are categorized as such: 66% in BiH, 72% in Serbia, 71% in Montenegro, and 75% among diaspora cases. Being positively and actively engaged with the radical milieu evidently had a great influence on Balkan foreign fighters.
For several cases it seems that a positive active relationship with the radical milieu may be sufficient for engagement in violent extremism. In , we identify four groupings (i.e. rows 5, 9, 41, and 43, shaded in light grey) representing fighters with no connection to an influencer but with a positive active relationship to the radical milieu. visualizes these set relations among foreign fighters, displaying the large number (93) of individuals evidently unconnected to either of the two predominant Islamist influencers in BiH.Footnote39
Figure 4. Set relations of foreign fighters, individuals with a positive active relationship to the radical milieu, individuals connected to imamovíc, and individuals connected to Bilal B. (i.e. in mvQCA denotation: ROLE[1]*INF[1]*INF[2]*RADMIL[1]).
![Figure 4. Set relations of foreign fighters, individuals with a positive active relationship to the radical milieu, individuals connected to imamovíc, and individuals connected to Bilal B. (i.e. in mvQCA denotation: ROLE[1]*INF[1]*INF[2]*RADMIL[1]).](/cms/asset/6d4f35a8-0484-4091-9587-6df4bcffc429/uter_a_2213967_f0004_b.jpg)
This pattern may signal more diverse radicalization trajectories, including individuals being inspired by various forms of online propaganda disseminated by radical influencers, without having in-person socialisation with them. Information for many of the cases in the dataset has not been obtained, and thus it is a challenge to distinguish between various radicalisation trajectories in a more specific manner. But many of these cases speak to the localness of foreign fighter recruitment. These individuals’ engagement in violent extremism is suggestive of a different form of radicalization, through peer-to-peer socialization. While we cannot rule out that some of these individuals were in fact connected to an influencer and any evidential basis was overlooked in data collection, several cases support the former conclusion. For example, Individual 1, who received a one-year prison sentence in 2016, went to Syria in March 2013 and spent three months there. In 2016, the BiH Prosecutor’s Office reached a plea bargain with Individual 2 and Individual 1, who pleaded guilty to organizing a terrorist group and assisting in the departure of BiH citizens to Syria and Iraq. There is no data indicating that he was linked to any major influencer—but peer-to-peer socialization was evident.
Consider the example of Individual 4, uniquely covered by row five in , who was previously in custody (in 2009–2010) for terrorist activity. His time in detention allowed him to be networked and active in the radical milieu without affiliation to an influencer. Another case, Individual 5, was a leader of a small mujahideen group who had fought in the BiH army and later trained in Germany before travelling to Syria and dying in late 2014. Individual 5 was essentially a minor-influencer, the leader of a cluster of fighters. This also seems to be the pattern for Individual 6, represented by row nine in , who helped several individuals from Montenegro travel to Syria to fight for IS. His case is suggestive of the structure of foreign fighter interconnectedness: a network-mapping approach would likely reveal large hubs around the main influencers like Bilal B. and Nusret I., and small clusters of individuals, like those connected to Individual 5 and Individual 6.
Although exceptional, some females who travelled to Syria had positive active relationships to the radical milieu and their own connections to radical influencers. Take the example of Individual 8, represented by row 26. Though she was not a fighter, several sources point to her battlefield activism, including military training and propaganda. She is the only woman in the dataset with a “double role.” According to data from Vlado Azinović’s reports, Individual 8 was in touch with Bilal B. before going to Syria.Footnote40 Witness testimony reported that Individual 8 visited Bilal B. on several occasions in the autumn of 2013 in his capacity as a spiritual authority to “cast jinn from her.”Footnote41 Shortly thereafter, Individual 8 left her husband and two children (three and ten years old at the time). She married Individual 9, who had lived in France; they met on Facebook and married under Sharia law. Together, in November 2013, they travelled to Syria. At time of writing, Individual 8 is still in Syria, in the al-Hawl camp. This case illustrated the variations of relationships that individuals developed with the radical milieu before travelling to Syria and the multiple roles that they could perform in the conflict zone.
Influencers and Terrorist Group Affiliation
Radical influencers gained prominence in places where former members of the mujahideen unit (El Mudžahid) in the Bosnian War settled after the end of the conflict.Footnote42 The locations of postwar “Salafi villages” and informal prayer congregations overlap with locations where mujahideen were present during the Bosnian War; later, some were hotbeds of foreign fighter mobilisation for the Syrian War. Yet such spaces are not radicalisation venues by default. Their significance cannot be explained solely with structural factors; the role of radical influencers cannot be overlooked. Those individuals socialized in the radical milieu who eventually became foreign fighters received inspiration and encouragement from informal authority figures. A typical case is the one of Emrah F., who became the first Bosnian suicide bomber in Iraq, blowing himself up in August 2014 in Baghdad. Initially, he and his family travelled to Syria, where they spent around six months before the suicide attack. Emrah F. left from one of the Salafi villages in BiH, Ošve, and was the first to become a foreign fighter from this location. Before going to Syria, he was accused and later acquitted of helping an individual that gunman that fired on the U.S. Embassy in Sarajevo in 2011.
Whereas many fighters were deeply embedded in the radical milieu and may or may not have had a connection to a radical influencer, several others were primarily affected by influencers. Take the example of Individual 7, a young activist connected to the NGO Solidarnost (“Solidarity”) who became one of the most notorious voices of Bosnian jihadists in Syria. In a 2015 video he called for jihad locally in case prospective recruits were not able to travel to Syria. He was reportedly killed in March 2018. Individual 7 was not well integrated into the radical milieu prior to his departure to Syria. But he was connected to Bilal B., as he is originally from Bihać where Bilal B. was active; and he was a student at Faculty of Pedagogy in the same city where a few professors were allegedly keen on spreading ultra-conservative religious ideas. His trajectory does not involve integration into one of the Salafi villages or regular attendance at sermons given by prominent Salafi influencers. The NGO he worked for helps vulnerable and persecuted Muslims around the world through humanitarian aid. He did video editing for this organization and was apparently exposed to online content stressing the suffering of Muslims. His familiarity with Bilal B. and his preaching played an important role in his radicalization.
Influencers also had some effect in steering foreign fighters towards certain terrorist groups. and display a differentiation in fighters’ affiliations in their travel to Syria, to IS and JN. Clearly, IS had more success in mobilizing foreign fighters from the Balkans. But a greater proportion of fighters connected to Nusret I. were affiliated with JN. Bilal B. had stronger connections to IS.
Figure 5. Set relations of foreign fighters, individuals connected to Bilal B., individuals affiliated with Al-Nusra Front, and individuals affiliated with Islamic State (i.e. in mvQCA denotation: INF[2]*ROLE[1]*GROUP[2]*GROUP[1]).
![Figure 5. Set relations of foreign fighters, individuals connected to Bilal B., individuals affiliated with Al-Nusra Front, and individuals affiliated with Islamic State (i.e. in mvQCA denotation: INF[2]*ROLE[1]*GROUP[2]*GROUP[1]).](/cms/asset/cea21da2-0c87-43ea-ad4d-f59632727228/uter_a_2213967_f0005_b.jpg)
Figure 6. Set relations of foreign fighters, individuals connected to Nusret I., individuals affiliated with JN, and individuals affiliated with is (i.e. in mvQCA denotation: INF[1]*ROLE[1]*GROUP[2]*GROUP[1]).
![Figure 6. Set relations of foreign fighters, individuals connected to Nusret I., individuals affiliated with JN, and individuals affiliated with is (i.e. in mvQCA denotation: INF[1]*ROLE[1]*GROUP[2]*GROUP[1]).](/cms/asset/a90afe95-c23b-4f9c-9b82-942c10c2604d/uter_a_2213967_f0006_b.jpg)
and also visualize a double affiliation phenomenon: individuals affiliated with JN and IS. The simple explanation is that a number of foreign fighters initially joined JN and later switched to IS. Their relationship to the radical milieu before going to Syria may explain many individuals’ decision to become foreign fighters, as their social ties and networks likely drove radicalization processes, but this cannot explain the double affiliation of foreign fighters. Instead, demand and supply dynamics generated this pattern. On the supply side, domestically, there were ideological cleavages between radical influencers: some advocated for IS, others for JN. While Nusret I., the strongest voice encouraging fighters to join AN went to Syria himself in late 2013, Bilal B., one of the key proponents of IS, was arrested in September 2014. These developments diminished the effect of radical influencers pushing outbound fighters to one or the other group. Moreover, once fighters had travelled to the conflict zone their erstwhile influencers had no capacity to impact their battlefield decisions and possible changes of affiliation.
On the demand side, JN had a stronger presence in the initial phase of the conflict in Syria, while the IS was still building its ranks. The majority of departures of Bosnian foreign fighters happened in 2013 and early 2014 when the IS was in a process of consolidating. Since the “caliphate” was not proclaimed yet and the IS campaign was not that loud yet, those who traveled to Syria followed rather the narrative for helping the Syrian people in their fight against the regime of Bashar Al-Assad, and thus, joining AN was recognized as a legitimate choice of affiliation. At the later stage, when fights between IS and JN occurred in the battlefield, foreign fighters made choices based on their individual motivations, ideological convictions, group dynamics and relations with their commanders in the war theatre.
Foreign Fighters and Bosnian Diaspora
The role of diaspora actors in shaping the Bosnian radical milieu can be understood through the development of humanitarian activities during and after the Bosnian War. Support for jihadists throughout the region became particularly evident in the 1990s when Islamic charities based in Vienna used their facilities and resources to support the mujahideen fighting in Bosnia and later Kosovo. Humanitarian aid distributed in the war made possible the emergence of Salafi influencers abroad whose authority had become evident long before foreign fighters began their journey to Syria.
The radical milieu in Austria originated in the 1990s, consolidated in the 2000s, and became a strategic location for the mobilization of jihadists for Syria.Footnote43 After the Bosnian War, a few Bosnian Salafis who had immigrated to Austria, Germany, and Switzerland contributed to the establishment of the radical milieu in Bosnia. Their role was essential, as they raised funds, and gained the status of authority among Salafis in the Balkans. Radical influencers residing in Austria linked jihadists in Western Europa with those in the Balkans. Their role became particularly important in the recruitment of foreign fighters, as they could utilise the status as authority figures that they had cultivated among their followers for more than two decades.Footnote44 Due in large part to their work, Austria had one the highest per capita number of foreign fighters in the EU.
For instance, key to the foreign fighter mobilisation in Austria was the radical influencer Mirsad O. (known as Ebu Tejma) originally from Sandžak, Serbia, who was particularly influential among jihadists in Vienna, but also in the Balkans (Hahn 2019). His name is linked to the radicalization of two teenage girls, Sabina S. and Samra K., who were born to families of Bosnian refugees in Austria. The two were exposed to online propaganda about “jihad in Syria” and had attended prayers at the Altun-Alem Mosque in Vienna where Mirsad O. served as an imam. The circle around Mirsad O. had important logistic and financial responsibilities for the cause of jihad and maintained an extensive network with other terrorist cells across Europe. In fact, Mirsad O. was a contact person in Vienna for both Nusret I. and Bilal B. in Bosnia.
The role of diaspora-based radical influencers was inspirational to a large pool of followers. Small peer groups abroad did not always have “access” to radical influencers directly. These are individuals from Bosnian diaspora who joined IS as fighters and for whom there was evidence for prior radical socialization without being linked to any particular influencer. A telling example is the case of Individual 10, one of the most notorious Bosnian IS fighters, killed in Syria in 2014. Born in Bosnia, Individual 10 was only 16 years old when the Bosnian War began. In the 1990s, he fought in the ranks of the Army of the Respublika Srpska, along with his father. After the war, he fled to the United States where he worked as a driver. In 2011, he lost his job, his marriage fell apart, and he began to socialize in militant Salafi circles. He assembled a small cluster of IS sympathizers from the Bosnian diaspora in the U.S. In 2014, Individual 10 facilitated money transfers between individuals in the U.S. and IS forces in Syria, maintained contact with Bosnia Salafists on social media, and finally travelled to the war zone.
The importance of maintaining influence among Bosnian Salafists abroad is evidenced by the fact that at least 15% of the foreign fighters belonging to the Bosnian contingent departed from other countries. In our dataset there are 19 individuals who emerged from diaspora communities. The Bosnian radical milieu was linked to diaspora communities across Europe—not just in Germany and Austria. Take the example of Ismar M., who was killed in January 2014. According to the Italian police, he had been linked to Bilal B.’s network in Italy. He struggled with a drug addiction and asked Bilal B. for help. He lived in Italy with his wife and their back then 3-year-old son. After “spiritual treatment” offered and performed by Bilal B. in BiH, Ismar M. returned to Italy. Yet, by the end of 2013, he had departed for Syria with his son, without his wife’s consent. Three months later, Ismar M. was killed, and the child was adopted by the family of another fighter. This case shows that even though some fighters were not socially linked to radical milieus in the Balkans, they could establish contact with radical influencers through other forms of interaction.
Discussion
The concept of influence on radicalization and engagement in violent extremism has guided both the framework and empirical analysis in this paper. Several individuals in our analysis were influenced by the likes of Bilal B. and Nusret I.; several were affected by their socialization in the post-conflict radical milieu. But privileging one or the other of these factors would misleading. On the one hand, the global IS recruitment campaign from the early days of the caliphate in 2014 showed the power of the large-scale social media campaign that drew many people to Iraq and Syria. On the other hand, the clusters of foreign fighter departures once again revealed the power of social networks over ideology. While recruitment of IS foreign fighters was highly decentralized, local radical milieus secured both resilient social structures and authority, concentrated in influencers’ networks.
The presence and legacy of the Arab mujahideen, the ideologically conditioned humanitarian aid, and emergence of local Salafi influencers created conditions for a postwar radical milieu to grow significantly in the years after the Bosnian War. These factors impacted the way this community evolved and how it responded to the Syrian War. Local radical influencers supported by international charities (some of them linked to the global Islamist movement) promoted their own view of the postwar social order. They created and maintained social structures, such as radical settlements and informal prayer congregations where radical narratives could evolve and contribute to a resilient community of followers.Footnote45 While most people following Salafi ideas lived in peace and seclusion, a few cases of support for extremist activities by Salafi followers have shown structures linked to the radical milieu could also become a venue of extremist socialisation.
Our study shows that radical influencers exercised their authority by encouraging individuals to join the “cause of jihad” in Syria and often propelled the recruitment processes of Bosnian foreign fighters. Our analysis points to several important findings. First, although almost all Bosnian foreign fighters and their families were socialized into the radical milieu, many lacked social ties to radical influencers. However, this does not refute the argument that radical influencers had a strong inspirational role in recruitment processes; it is suggestive of the equifinality of radicalization and engagement in violent extremism: there are many pathways. For their part, radical influencers’ activism, both in person and on social media, provided their followers with multiple channels of exposure to Islamist propaganda. Radical influencers relied on various combinations of opportunities, structures, and cultural frames to mobilize support. This knowledge helps to identify who gets targeted to become a foreign fighter.
Second, the cases of individual foreign fighters reveal the characteristics of radical influencers, their ideological tenets, the violence of their rhetoric, and the extent of their influence. Our cases show that influencers are potent forces in the localities in which they operate, but they can engage and effect far flung diaspora communities as well.
Finally, the gender and demographic profiles of the recruited foreign fighters helps to unpack types of relationships with the radical milieu. Multiple cases indicate that these conditions cannot be used to assume that all men coded as “fighters” were actively linked to influencers and all women were passive followers of their actions. Overall, the research has demonstrated the potential of analyzing foreign fighters not only as individual actors, but also as part of a group phenomenon, with boundaries that are determined by pre-existing social relations.
Our analysis is limited by the omission of certain socio-economic factors. Although the role of poverty has been contested in the debate on the root causes of terrorism, the Bosnian contingent in the Syrian War was comprised of individuals from poor to middling socio-economic and educational backgrounds. Furthermore, Balkan jihadists emerge from societies in which social relations are defined by post-conflict fragility. There may be specific causal mechanisms linking domestic wars in the Balkans and foreign fighter mobilization: from inherited grievances to higher tolerance for violence in militarized societies and easy access to arms. Each of them needs to be tested in order to understand the impact of context on jihadist mobilization.
The article is a part of a larger in-depth investigation that asserts that the mobilization of foreign fighters in the Balkans emerged from the need to restore social order in post-conflict societies.Footnote46 Most fighters who originated from postwar Balkan societies did not have combat experience. Rather, they were socialized into local radical milieus that appeared as by-products of domestic wars. Those milieus are shaped and manipulated by radical influencers. Their informal authority has been readily “institutionalized” in societies marked by recent conflicts, as they offer a sense of belonging and community to those in need. The formation of post-conflict radical milieus constitutes a process in which a community is shaped, relations evolve, and people develop a sense of trust and loyalty. In this way, post-conflict radical milieus were formative to individuals’ decisions to travel to the IS caliphate and even bring their families.
Acknowledgements
This article has benefited greatly from feedback from several colleagues and reviewers. We want to thank participants of the Comparative Politics section of the Swiss Political Science Association Annual Congress in 2022. We also thank especially Ekaterina Paustyan and Jan Kovar for their invaluable comments on early drafts of this article, as well as two anonymous reviewers.
Disclosure Statement
No potential conflict of interest was reported by the author(s).
Notes
1 Vlado Azinović and Edina Bećirević, A Waiting Game: Assessing and Responding to the Threat from Returning Foreign Fighters in the Western Balkans (Regional Cooperation Council, 2017).
2 David Malet, Foreign Fighters: Transnational Identity in Civil Conflicts (Oxford: Oxford University Press, 2013), 8–9.
3 Petter Nesser, Islamist Terrorism in Europe (Oxford: Oxford University Press, 2018), 18–19.
4 Thomas Hegghammer, “Terrorist Recruitment and Radicalization in Saudi Arabia,” Middle East Policy 13, no. 4 (2006): 39–60; Haroro J. Ingram, The Charismatic Leadership Phenomenon in Radical and Militant Islamism (Routledge, 2016); Peter R. Neumann, Radicalized: New Jihadists and the Threat to the West (Bloomsbury Publishing, 2016).
5 Asya Metodieva, Foreign Fighters and Radical Influencers: Radical Milieus in the Postwar Balkans (Routledge, 2022).
6 See, e.g., Vlado Azinović, “The Foreign Fighter Phenomenon and Radicalization in the Western Balkans: Understanding the Context, 2012-2016,” in Between Salvation and Terror: Radicalization and the Foreign Fighter Phenomenon in the Western Balkans (Atlantska inicijativa: Udruženje za promicanje euroatlantskih integracija BiH, 2017), 9–20; Tatyana Dronzina and Akmaral Medikhanova, “Repatriation of Migrants to ISIS: The Experience of Four States from the Western Balkans,” Balkan Social Science Review 17 (2021): 239–265; Tatyana Dronzina and Yavor Raychev, “Women from Kosovo in ISIS: Quest for Identity, Community and Protagonism,” Sociological Problems 51 (2019): 373–388; Arolda Elbasani and Olivier Roy, “Islam in the post-Communist Balkans: Alternative Pathways to God,” Southeast European and Black Sea Studies 15, no. 4 (2015a): 457–471; Arolda Elbasani and Oliver Roy, The Revival of Islam in the Balkans (New York: Springer, 2015b); Kolë Krasniqi, Islamist Extremism in Kosovo and the Countries of the Region (Springer Nature, 2019); Shpend Kursani, “Salafi Pluralism in National Contexts: The Secular State, Nation and Militant Islamism in Kosovo, Albania, and Macedonia,” Southeast European and Black Sea Studies 18, no. 2 (2018): 301–317; Ina Merdjanova, Rediscovering the Umma: Muslims in the Balkans between Nationalism and Transnationalism (Oxford: Oxford University Press, 2016).
7 Since we have categorical variables set-theoretic techniques are most appropriate here. Scalar data would be better suited to cluster analysis or factor analysis.
8 Though we do not offer a causal analysis—our dataset consists only of individuals that travelled to Syria, no ‘negative’ outcome cases that would enable a degree of causal inference—the use of QCA techniques is appropriate because it is a methodology that agrees with the ontological presumptions (Peter Hall, “Aligning Ontology and Methodology in Comparative Politics,” in Comparative Historical Analysis in the Social Science (Cambridge: Cambridge University Press, 2003), 373–404) about radicalization and engagement in violent extremism: it is conjuncturally caused (Martha Crenshaw, “The Causes of Terrorism,” Comparative Politics 13, no. 4 (1981): 379–399; Michael A. Jensen, Anita Atwell Seate, and Patrick A. James, “Radicalization to Violence: A Pathway Approach to Studying Extremism,” Terrorism and Political Violence 32, no. 5 (2020): 1067–1090).
9 Rik Coolsaet, What Drives Europeans to Syria, and to IS? Insights from the Belgian case (Academia Press, 2015); Rik Coolsaet, ‘All Radicalisation is Local’: The Genesis and Drawbacks of an Elusive Concept. Vol. 84. (Egmont-Royal Institute for International Relations, 2016); Timothy Holman, “Belgian and French Foreign Fighters in Iraq 2003–2005: A Comparative Case Study,” Studies in Conflict & Terrorism 38, no. 8 (2015): 603–621; Nesser, Islamist Terrorism in Europe; Peter R. Neumann and Brooke Rogers, Recruitment and Mobilisation for the Islamist Militant Movement in Europe (London: ICSR, King’s College London, 2007); Peter R. Neumann, Prisons and Terrorism: Radicalisation and de-radicalisation in 15 Countries (London: ICSR, King’s College London, 2010); Peter R. Neumann, Joining al-Qaeda: Jihadist Recruitment in Europe. No. 399. (Routledge, 2008); Neumann, Radicalized: New Jihadists and the Threat to the West; Thomas Renard and Rik Coolsaet, “Returnees: Who are they, Why Are They (Not) Coming Back and How Should We Deal With Them,” Assessing Policies on Returning Foreign Terrorist Fighters in Belgium, Germany and the Netherlands 101 (2018).
10 Bruce Hoffman, “Al Qaeda, Trends in Terrorism, and Future Potentialities: An Assessment,” Studies in Conflict & Terrorism 26, no. 6 (2003): 429–442.
11 Marc Sageman, Leaderless Jihad: Terror Networks in the Twenty-First Century (University of Pennsylvania Press, 2011).
12 Nesser, Islamist Terrorism in Europe, 1.
13 Alexander Meleagrou-Hitchens, Seamus Hughes, and Bennett Clifford, Homegrown: ISIS in America (Bloomsbury Publishing, 2020).
14 Marc Sageman, Misunderstanding Terrorism (University of Pennsylvania Press, 2017); Nesser, Islamist Terrorism in Europe; Olivier Roy, Jihad and Death: The Global Appeal of Islamic State (Oxford: Oxford University Press, 2017); Marc Sageman, Understanding Terror Networks (University of Pennsylvania press, 2004).
15 Roberto Fernandez and Doug McAdam, “Multiorganizational Fields and Recruitment to Social Movements,” International Social Movement Research 2 (1989): 315–343; David Knoke and Nancy Wisely, “Social Movements,” Political Networks (1990): 57–84; Doug McAdam and Ronnelle Paulsen, “Specifying the Relationship between Social Ties and Activism,” American Journal of Sociology 99, no. 3 (1993): 640–667.
16 Hughes Meleagrou-Hitchens and Clifford, Homegrown: ISIS in America.
17 Coolsaet, What Drives Europeans to Syria, and to IS? Insights from the Belgian case; Coolsaet, ‘All Radicalisation Is Local’: the Genesis and Drawbacks of an Elusive Concept; Robert S. Leiken, “Europe’s Angry Muslims,” Foreign Affairs 84 (2005): 120; Nesser, Islamist Terrorism in Europe; Neumann, Radicalized: New Jihadists and the Threat to the West; Matteo Vergani, Muhammad Iqbal, Ekin Ilbahar, and Greg Barton, “The Three Ps of Radicalization: Push, Pull and Personal. A Systematic Scoping Review of the Scientific Evidence about Radicalization into Violent Extremism,” Studies in Conflict & Terrorism 43, no. 10 (2020): 854–85; Lorenzo Vidino, “Aims and methods of Europe’s Muslim Brotherhood,” Current Trends in Islamist Ideology 4 (2006): 22–45.
18 Chelsea Daymon, J. H. de Roy van Zuijdewijn, and David Malet, “Career Foreign Fighters: Expertise Transmission Across Insurgencies,” Career Foreign Fighters: Expertise Transmission Across Insurgencies (2020); Mohammed Hafez, “Martyrs without Borders: Iraq’s Foreign Fighters and the Third Generation of Global Jihad’,” National Consortium for the Study of Terrorism and Responses to Terrorism (2012).
19 Ingram, The Charismatic Leadership Phenomenon in Radical and Militant Islamism, 27.
20 Edwin Bakker and Roel De Bont, “Belgian and Dutch Jihadist Foreign Fighters (2012–2015): Characteristics, Motivations, and Roles in the War in Syria and Iraq,” Small Wars & Insurgencies 27, no. 5 (2016): 837–857; van Zuijdewijn Daymon and Malet, “Career Foreign Fighters: Expertise Transmission Across Insurgencies”; Hafez, “Martyrs without Borders: Iraq’s Foreign Fighters and the Third Generation of Global Jihad’”; Sean C. Reynolds and Mohammed M. Hafez, “Social Network Analysis of German Foreign Fighters in Syria and Iraq,” Terrorism and Political Violence 31, no. 4 (2019): 661–686; Pieter Van Ostaeyen, “Belgian Foreign Fighters in Syria and Iraq–May 2016,” in Not only Syria? The Phenomenon of Foreign Fighters in a Comparative Perspective (IOS Press, 2017): 40–51.
21 Neumann, Radicalized: New Jihadists and the Threat to the West, 95.
22 Neumann and Rogers, Recruitment and Mobilisation for the Islamist Militant Movement in Europe, 36–37.
23 Stefan Malthaner and Peter Waldmann, “The Radical Milieu: Conceptualizing the Supportive Social Environment of Terrorist Groups,” Studies in Conflict & Terrorism 37, no. 12 (2014): 979–998; Zsuzsanna Vidra and Michael C. Zeller, Preventing Violent Extremism: A Delicate Balance (Firenze: European University Institute: Robert Schuman Centre, 2021).
24 Neumann and Rogers, Recruitment and Mobilisation for the Islamist Militant Movement in Europe.
25 Malthaner and Waldmann, “The Radical Milieu: Conceptualizing the Supportive Social Environment of Terrorist Groups.”
26 Metodieva, Foreign Fighters and Radical Influencers: Radical Milieus in the Postwar Balkans.
27 See Hutter, Swen, Protest event analysis and its offspring. In Methodological Practices in Social Movement Research (Oxford: Oxford University Press, 2014): 335–367.
28 Cf. Weggemans, Daan, Marieke Liem, and Marieke van der Zwan, “A Family Affair? Exploratory Insights into the Role of Family Members of those who Joined Jihadist Groups,” Security Journal 35, no. 3 (2022): 849–862.
29 We presume that none—or at least a negligible number—of the individuals in the dataset had a ‘negative relationship,’ whether passive or active, with the radical milieu.
30 There is a degree of interdependence between being connected to a radical influencer and the broader relationship to the radical milieu. We offer further clarification in the data description in Appendix A.
31 Charles C. Ragin, Redesigning Social Inquiry: Fuzzy Sets and Beyond (Chicago: University of Chicago Press, 2009); Carsten Q. Schneider and Claudius Wagemann, Set-Theoretic Methods for the Social Sciences: A Guide to Qualitative Comparative Analysis (Cambridge: Cambridge University Press, 2012).
32 Schneider and Wagemann, Set-Theoretic Methods for the Social Sciences: A Guide to Qualitative Comparative Analysis, 276.
33 As a check on our analysis, we also applied a crisp-set analysis of the data. This technique did not substantively change the results, apart from providing less specificity regarding some categories. We report the csQCA results in Appendix C.
34 Also, particularly in cases of individuals with relevant criminal convictions and of unauthorised minors, the outcome of ‘travel’ represents a state security failure.
35 Cf. Metodieva, Asya, “The Radical Milieu and Radical Influencers of Bosnian Foreign Fighters,” Studies in Conflict & Terrorism (2021): 1–21.
36 Metodieva, Foreign Fighters and Radical Influencers: Radical Milieus in the Postwar Balkans.
37 This minimization is ‘conservative,’ meaning that none of the truth table rows for which we have no empirical manifestations were used to minimise the data. For more on solution types produced by minimization, see Schneider and Wagemann, Set-Theoretic Methods for the Social Sciences: A Guide to Qualitative Comparative Analysis.
38 Because there is no variation in the outcome in the data, all groupings are completely consistent (normally denoted as ‘inclS’) and all are completely relevant (normally denoted as ‘PRI’).
39 Comparing these cases with other individuals with a positive active relationship to the radical milieu but who did not become foreign fighters would offer good tests of this variable’s causal impact.
40 Azinović, “The Foreign Fighter Phenomenon and Radicalization in the Western Balkans: Understanding the Context, 2012–2016.”
41 Azinović and Bećirević, A Waiting Game: Assessing and Responding to the Threat from Returning Foreign Fighters in the Western Balkans.
42 Sead Turčalo and Nejra Veljan, Community Perspectives on the Prevention of Violent Extremism in Bosnia and Herzegovina (Atlantska inicijativa, 2018).
43 Johannes Saal and Felix Lippe, “The Network of the November 2020 Vienna Attacker and the Jihad Threat to Austria,” CTC Sentinel 14, no. 2 (2021).
44 Dzeneta Karabegović and Asya Metodieva, Deradicalization of Foreign Fighters and the Agency of Diaspora, Special Issue. Nordic Journal of Migration Research (forthcoming).
45 Metodieva, Foreign Fighters and Radical Influencers: Radical Milieus in the Postwar Balkans.
46 Ibid.
47 Jacob N. Shapiro, “The Terrorist’s Dilemma,” in The Terrorist’s Dilemma (Princeton University Press, 2013).
48 Elizabeth Pearson and Emily Winterbotham, “Women, Gender and Daesh Radicalisation: A Milieu Approach,” The RUSI Journal 162, no. 3 (2017): 60–72.
Appendix A:
Further data description
Several biographical attributes were coded for each individual in the dataset:
year of birth,
sex,
country and locality of residence,
year of travel to Syria,
role in the conflict (i.e., fighter, wife, child, or recruiter),
group of affiliation in Syria (Islamic State, al-Nusra, or other), and
status as of April 2021 (i.e., killed, returned to country of origin, still in Syria, or unknown).
Connection to Radical Influencers
Coding connection to Islamist influencers Nusret I. and Bilal B. (and in a handful of instances to the el-Furkan mosque and Idriz B. in Novi Pazar, Serbia) is somewhat inexact. Previous research shows that ideological groups, particularly if they are part of a larger movement, are inspired by the concept of a common destiny and the images of a shared enemy whereas their organizational structure may have a good deal of flexibility.Footnote47 We can be confident of some individuals’ connection to one or the other influencers, coded as such in the dataset, but many foreign fighters are not directly linked to radical influencers. Of those, typically there was evidence testifying to activism and a strong ideological commitment of foreign fighters before their departure to Syria. As ever with partially hidden communities, there may be connections and relationships that remain invisible to research inquiry. We account for this possibility in the discussion of our analysis.
Gender and Relationships to the Radical Milieu
Concerning individuals’ relationship to the radical milieu, we recognise that gender plays a strong role in how individual relationships with the radical milieu were shaped due to ways in which the IS framed recruitment and propaganda messaging towards men and women, different social expectations of both genders, different access to public space, and different gendered personal drivers that people may have.Footnote48 Consequently, most men in the sample developed positive active relationships with the radical milieu, whereas most women had positive passive relationships with the community.
The Distinction between Connection to Influencers and Relationship to the Radical Milieu
The theoretical distinction between being linked to an influencer and to the radical milieu focuses on immediate social ties to a radical influencer versus social ties to the broader community, including through social media exposure to extremist narratives, family dynamics, and peer socialization. In other words, there is a partial set relationship between these variables: if an individual is connected to a radical influencer, then they have a relationship to the radical milieu. That relationship may be active or passive, but in either case it plainly exists. Analytically separating connection to influencers from relationship to the radical milieu allows us to distinguish different patterns of radical socialization.
Data Imputation
To perform a mvQCA with our dataset, we excluded four individuals that were connected to more than one influencer, eleven individuals for whom we were missing information about their origins and/or role, and the only individual in our dataset from Kosovo. Furthermore, we performed two data imputations on wives and children in the dataset: first, we attributed to them the husband’s group and influencer affiliations; second, if a fighter had a positive active relationship to the radical milieu, their wives and children, unless other evidence was available, were coded as having a “positive passive” relationship.
Appendix B:
mvQCA v1
Outcome:
TRAVEL = Travelled to Syrian conflict zone (1 = yes)
Conditions:
ORIGIN = place of origin: 0-elsewhere(diaspora), 1-BiH, 2-Serbia, 3-Montenegro ROLE = role: 0-none, 1-fighter, 2-wife, 3-child, 4-recruiter
GROUP = Syria group affiliation: 0-none, 1-IS, 2-AN, 3-both
INF = connection to influencer: 0-none/uncertain, 1-Nusret I., 2-Bilal B., 3-diaspora, 4-el-Furkan mosque
RADMIL = relationship with radical milieu: 0-null/negative, 1-positive active, positive passive (excluded)
FAM = Accompanied/joined by family: 0-no, 1-yes
From these conditions there are 4*5*4*5*3 = 1200 logical possibilities.
Truth table for mvQCA
Table B1. Unabridged solution Table for mvQCA version 1.
Appendix C.
csQCA
Analysis with “FAM” condition removed as it somewhat correlates with empirical in- formation of “FIGHTER”
Conditions:
FIGHTER = a fighter, rather than an accompanying woman or child IS = fighter affiliated with Islamic State
AN = fighter affiliated with Al Nusra
POSACT = Positive active relationship with radical milieu, rather than positive passive or null
Nusret I. = connected to Nusret I. (influencer) and/or the Gornja Maoča community BO = connected to Bilal B. (influencer) and/or the Ošve community
This means that if all these conditions are used there are (26) 64 logical possibilities. The crisp-set configurational analysis included six sets: (1) FIGHTER, referring to whether individuals travelled to Syria to fight in the war, (2) IS, referring to whether an individual was affiliated to the Islamic State group, (3) AN, referring to whether an individual was affiliated with the Al-Nusra Front, (4) POSACT, referring to whether an individual had a “positive active” relationship to the radical milieu in their place of origin, (5) IGM, referring to whether an individual was connected to Nusret Imamovíc, and (6) BO, referring to whether an individual was connected to Bilal B. Analyzing the observations with these sets, applying QCA minimization procedures, reveals configurations, groupings, of cases to guide interpretation of the data.
Table C1. Calibration summary for csQCA (all cases from the origin of Bosnia.).
Standard QCA practice is first to perform an analysis of necessity, identifying any conditions or pairs of conditions that are always or nearly always associated with the outcome. Since our data includes no variation in the outcome—again, all individuals in the dataset travelled to Syria—we cannot actually test the conditions’ necessity, but we can determine if any are pervasive within the data. No atomic conditions appear to be necessary in this sense; in other words, there is no condition in our analysis for which (virtually) all individuals are members. What is more, no binary combinations (see ) are necessary. This suggests, in line with previous research findings (Jensen Seate, & James, 2020), there are many pathways and processes radicalizing to the point of engaging in violent extremism. Furthermore, several individuals in the dataset had no apparent positive active relationship with the radical milieu, nor connections to radical Islamist influencers. Yet they too travelled to Syria. These cases, where neither of the conditions that we presume are causally significant, invite closer inspection (see below).
Table C2. Unabridged solution table for csQCA. A tilde (∼) in front of a condition refers to the condition’s absence.
Necessity Analysis
No atomic conditions were necessary. There are 13 binary combinations that appear necessary, but multiple cases for each violate the suggested necessity relationship. This can be checked with the pimplot function, producing plots of all 13 specious necessity relationships. Cases in the upper left-hand quadrant have the outcome, but not the necessary combination.
Table C3. Necessity analysis.