Introduction
State repression and targeting of individuals based on their language, religion, and ethnicity is a recurrent phenomenon in global politics, transcending the boundaries between democracies and dictatorships. While there are records of such repression in both regimes, its occurrence is more frequent in non-democratic environments, often because of the reduced political costs associated with such measures (Davenport Reference Davenport2007). Researchers encounter significant challenges when investigating such repressive events in the latter where civil and political rights are not consistently guaranteed (Morgenbesser and Weiss Reference Morgenbesser and Weiss2018). The inherent opacity of these regimes presents a formidable obstacle to data access, thus further complicating the research landscape. This has prompted scholars to use a very diverse set of theoretical frameworks, methodologies, and data collection strategies to overcome these research ordeals. Consequently, the literature on ethno-religious repression in non-democratic regimes has frequently led to inconsistencies regarding the causes and consequences of these human rights violations. As a result, conducting a systematic review of the literature may help to identify gaps, weaknesses, and trends in current findings and guide future research in this area (Munn et al. Reference Munn, Micah, Stern, Tufanaru, McArthur and Aromataris2018).
To the best of our knowledge, this is the first systematic review of ethno-religious repression in non-democratic regimes, using the validated PRISMA flow method. Previous studies have conducted reviews in a non-systematic way, examining repression in both democratic and non-democratic regimes without specifically addressing ethno-religious minorities (Davenport Reference Davenport2007; Honari Reference Honari2017), or focused on only some specific forms of state repression against ethno-religious minorities, such as ethnic cleansing (Bulutgil Reference Bulutgil2018), genocide (Luft Reference Luft2015), or transnational repression (Dukalskis et al. Reference Dukalskis, Furstenberg, Gorokhovskaia, Heathershaw, Lemon and Schenkkan2022).
Therefore, the aim of the present systematic review is to better understand the specific causes, consequences, and endogenous relationships of all different forms of state repression against ethno-religious minorities in non-democratic settings. To do so, we analyzed all articles on the topic indexed in the Social Science Citation Index of the Web of Science database, published in English, Spanish, Japanese, Korean or Chinese between January 1990 and December 2022 (n=169).
Methodologically, we find two major types of research on the topic: comparative studies and case studies. Regarding the former, most articles in our sample used large N comparative analyses that include both democratic and non-democratic contexts. With regard to case studies, they mainly concentrate on Sub-Saharan African countries and East Asian states, with a special focus on Rwanda and China. In terms of data collection, qualitative research employing discourse analysis of government sources dominates the literature, while quantitative research predominantly uses cross-national time-series of violent events.
Regarding substantive findings, the literature has identified ethnic and religious fractionalization, economic crises, and ethnic activism as principal causes of state repression against ethno-religious minorities. Identitarian, physical and psychological effects on individuals, impacts on repertoires and internal structure of ethnic activism, and varied transitional justice politics emerge as key consequences. Additionally, scholars often identify an endogenous relationship between ethnic activism and state repression.
Analytical approach
To conduct our systematic review of state repression against ethno-religious minorities in non-democratic settings, we employed PRISMA flow methodology developed by Moher et al. (Reference Moher, Liberati, Tetzlaff, Altman, Antes, Atkins and Barbour2009). Accordingly, we systematically searched for articles published in English, Spanish, Japanese, Korean, or Chinese languagesFootnote 1 from the Web of Science (WoS) database under the Social Science Citation Index (SSCI) ranging from January 1, 1990, to December 31, 2022. We chose as starting year 1990 due to the significant geopolitical shifts and ethnic conflict during this decade, marked by the collapse of the Soviet Union and the Yugoslavia’s War (see Supplementary Materials pages 3-4 for a further explanation on this methodological decision).
We identified peer-reviewed articles that addressed the repression of domestic ethnic groups identified as such in the GROWup Database. For a detailed conceptualization of what we understand for ethnic groups see Section I of the Supplementary Materials. Since this article focuses on coercive state practices, our conceptualization of repression follows Davenport’s (Reference Davenport2007) criteria, and considers all violations of integrity and intimacy of the person, including: ‘harassment, surveillance/spying, bans, arrests, torture, and/or mass killing by government agents and/or affiliates within their territorial jurisdiction’. As a result, we do not analyze papers focusing solely on discrimination, as our interest lies in more direct forms of state coercion rather than systemic or structural inequalities. While discrimination is a frequent form of interaction between the state and minoritarian ethnic groups, it does not necessarily meet the threshold of physical or coercive violations, which are the primary focus of this study. To maximize the number of peer-reviewed articles, search terms were combined with the Boolean operator ‘AND’, in the following three strategies: ’repress*’ AND ’ethnic*’ (321 articles), ’genocide*’ AND ’ethnic*’ (305 articles), and ’persecut*’ AND ’ethnic*’ (93 articles). These search criteria yielded an initial set of 719 articles (see Figure 1). Section II of the Supplementary Material offers additional insights on inclusion and exclusion criteria.

Figure 1. PRISMA flow diagram
Source: The authors
In the identification phase, we excluded repeated articles (n=19) and those that did not meet the initial WoS filters (n=56). In the first screening, we reviewed all abstracts to ensure they addressed state repression of domestic ethno-religious minorities following our conceptualizations of repression and ethnic groups detailed above. We specifically excluded all articles (n=198) that did not address state repression against either civilians (i.e. those studies focused on repression against non-state armed groups therefore dealing with intrastate ethnic conflicts or terrorist organizations) or ethnic groups (i.e. articles centered in state repression against LGTBQI+ groups). Additionally, we excluded presentations of databases, indexes, or rational choice models that lacked empirical analysis, as well as non-empirical articles that focused on theoretical or philosophical essays (n=53). Furthermore, articles discussing the repression of immigrants and refugees were removed from our database to align with our focus on domestic ethno-religious minorities (n=70).
Later, we established a strict exclusion criterion by removing articles that focused on political exclusion or discrimination (n=16), rather than direct, coercive state practices or violent repression. We do so for two reasons. First, articles focused on systemic discrimination, or sociopolitical marginalization do not align with Davenport’s (Reference Davenport2007) definition of repression, and second, they are not easily attributable to a coercive state-driven policy but could rather be the outcome of pervasive social inequalities and historical grievances. As a result, studies examining systemic exclusion from political representation, unequal access to resources, or societal discrimination were excluded. We also excluded articles that specifically dealt with repression during the COVID-19 pandemic, as the global community faced confinement and repression due to health security concerns (n=2). After applying all the above criteria, we selected 308 articles for a second round of screening.
Since we are specifically interested in non-democratic regimes, for the second screening of the literature review, we read the full papers analyzing countries that were non-democratic in the period 1990-2022. As a result, we excluded all papers that examined state repression before 1990 (n=54) and all papers examining state repression after 1990 in – using criteria from Freedom House Index – democratic countries (n=38). After excluding articles that were not available online (n=20) or did not address state ethno-religious repression in the text (n=24), we fully analyzed 169 articles.
For each article, we gathered data on its publication year, field of study, language, and journal. Then, we analyzed the papers, looking at the methods and types of analysis used, the cases studied, the most utilized databases, and the main approaches to the causes, consequences, and endogenous relationships of this phenomenon.
Results
Publication details
Our sample shows a growing interest in the subject since the beginning of the period analyzed, most notably since 2018 onwards, 2019 being the year with the maximum number of publications (n=24), reaching 14.2% of the sample (see Figure 2).

Figure 2. Published articles per year.
Source: The authors
Most of the articles were published in Nationalities Papers, The Journal of Nationalism and Ethnicity (n=11), Journal of Conflict Resolution (n=11), and Ethnic and Racial Studies (n=7) (see Figure 3). According to WoS field classification around 27.2% of the articles were published in Area Studies journals (n=46), 23.6% in International Relations journals (n=40), and 12.4% in Political Science journals (n=21) (see Section III of Supplementary Materials). Finally, most of the articles were written in English (n=168), while only one was written in Spanish.

Data, concepts, and methods
Regarding methodology, out of the total number of articles, 54.4% used qualitative methods (n=92). On the other hand, 37.8% of the articles focused on quantitative methods (n=64), with special focus on cross-national time-series studies of violent events (n=32). Additionally, 13.7% of the sample employed the content analysis method (n=15) or mixed it with discourse analysis (n=7) about government discourses and propaganda. Concerning analyzed cases, when considering case studies, Rwanda had the highest number of studies (n=25), followed by China (n=18), and Myanmar (n=9), making up for 30.6% of the sample.
In terms of data collection, the most used databases were those proposed by Minorities at Risk (n=14), Political Terror Scale (n=10), and UCD/PRIO Armed Conflict Dataset (n=8). Section IV of the Supplementary Material displays the concepts and dimensions of repression against ethno-religious minorities measured by these databases. Concerning the measurement of repression it is categorized into three subgroups: cultural repression (e.g., religious persecution, anti-conversion laws, heritage destruction, cultural genocide), activism repression (including intimidation of activists, political imprisonment, presence of security forces, surveillance, and violence), and violation of individual rights related to human dignity and physical integrity (e.g., rape, forced sterilization, torture, public executions, genocide, and mass killings)
Key topics
After analyzing all the articles included in this review, we classified them into three areas of analysis, considering the focus of the research: causes, consequences, and endogenous relationships. The selection of these analytical categories was inspired by Bulutgil’s (Reference Bulutgil2018) review, which centered on the causes of ethnic cleansing, and Honari’s (Reference Honari2017) review, which studied the citizens’ response to repression. Yet, we found a considerable number of articles that investigated bidirectional relationships between state repression and different socio-political factors. Thus we created a third category for endogenous relationships.
Main causes of state repression
The literature has mainly focused on three sets of causes that prompt state ethno-religious repression: socio-demographic variables, economic and political junctures, and the role of ethnic activism as an excuse for repressive measures. Additionally, dehumanizing narratives and state propaganda are acknowledged as reinforcing causes of repression.
First, regarding ethno-demographic backgrounds, the literature finds a consistent positive relationship between ethnic and religious fractionalization and state repressive behavior (Ruddell and Urbina Reference Ruddell and Urbina2004; Walker Reference Walker2007; Nichols Reference Nichols2018; Saiya and Manchanda Reference Saiya and Manchanda2019), suggesting that higher levels of ethno-religious diversity are positively associated with increased likelihood of repression. However, despite the extensive focus on fractionalization, the literature has reported no findings of a causal order relationship that could suggest that ethnolinguistic diversity actually leads to state repression (Walker Reference Walker2007; de Soysa and Almås Reference de Soysa and Almås2019).
Second, studies examining the economic variables have focused on variables related to both the economic cycle and the economic inequality of ethnic groups in the investigated countries. Scholars have found that during economic and political crises (when dissatisfaction with government usually increases), state leaders tend to create “internal diversionary wars” by targeting minority groups as terrorists, promoting ethnic polarization, and using domestic force against them (Tir and Jasinski Reference Tir and Jasinski2008; Klein and Tokdemir Reference Klein and Tokdemir2019). Additionally, some studies report that living close to profitable natural resources is often related to state ethno-state repression such as forced displacement of Indigenous communities from their territories without compensation (Munzert Reference Munzert2019), and perpetration of attacks and mass killings on ethnic minorities (Olsson and Siba Reference Olsson and Siba2013; Esteban, Morelli, and Rohner Reference Esteban, Morelli and Rohner2015). However, no discernible relationship was found between economic inequality and state repression of ethno-religious minorities (Besançon Reference Besançon2005; Bulutgil Reference Bulutgil2015).
Third, the literature has established that repression is more frequent against ethno-religious minority groups that have a long history of protest and rebellion (Beiser-McGrath Reference Beiser-McGrath2019). Yet, the repression of ethnic activism is contingent upon certain government features and the historical context of inter-ethnic relations. For instance, state repression of ethnic protest is more frequent in countries ruled by ethnically homogeneous governments (Hendrix and Salehyan Reference Hendrix and Salehyan2017; Reference Hendrix and Salehyan2019; Manekin and Mitts Reference Manekin and Mitts2022). Similarly, research shows that African regimes with a history of military-ethnic factionalism and larger ethnic ruling coalitions are less likely to use repression against ethnic movements (Hendrix and Salehyan Reference Hendrix and Salehyan2017; Reference Hendrix and Salehyan2019).
Finally, although limited research has explored the impact of the dehumanizing narratives and propaganda as causes of violence and genocide (Straus Reference Straus2007; Baker Reference Baker2013; Baisley Reference Baisley2014; Kiper Reference Kiper2022), all articles that do so consistently agree in identifying these narratives as secondary causes, while identifying ethnic fractionalization, political junctures (i.e. presidential assassination, coup d’état, civil war) and state strong capacities in local areas as principal causes.
Main consequences of state repression
The consequences of state repression against ethno-religious minorities identified by the existing literature include individual effects (physical and psychological harms), group effects (identity transformation and political behavior of groups) and systemic effects (notably, impacts on transitional justice policies).
First, regarding the effects of repression on individuals, certain forms of repression such as “genocidal rape” are found to provoke severe psychological and physical harm to the victims themselves and other members of the ethnic group, forcing the displacement and death of the victims in several cases (Hutchinson Reference Hutchinson2018; Pinaud Reference Pinaud2020; Anwary Reference Anwary2022).
Second, in relation to the effects on the ethnic groups themselves, the literature suggests that repression prevents ethno-religious minorities from initiating nonviolent campaigns due to pessimism about widespread participation and fear of punishment (Arriola Reference Arriola2013; Carter and Carter Reference Carter and Carter2022). Still, many studies have examined how ethno-religious minorities employ cultural repertoires (Baranovitch Reference Baranovitch2007; Karimi Reference Karimi2017) and online platforms (Vergani and Zuev Reference Vergani and Zuev2011; Lhagyal Reference Lhagyal2021; Yusupova Reference Yusupova2022), to express and communicate their grievances, and evade state forces and censorship. Furthermore, repression is found to decrease the internal unity of ethnic movements (McLauchlin and Pearlman Reference McLauchlin and Pearlman2012). When it comes to group identity, while some scholars argue that “culture genocide” politics lead to a loss of identity of the ethno-religious minority (Rosenberger Reference Rosenberger2007; Grose Reference Grose2020), other authors suggest that they have reinforced or even radicalized ethnic identity (Omelicheva Reference Omelicheva2010; Hintz and Quatrini Reference Hintz and Quatrini2021).
Finally, regarding consequences for the political system, severe forms of repression seem to not only reinforce the perpetrator’s group identity, but also to contribute to the process of ethnic ranking and consolidation of ethnicized social classes (Trenholm et al. Reference Trenholm, Olsson, Blomqvist and Ahlberg2016; Pinaud Reference Pinaud2020; Zenz Reference Zenz2021). Scholars have also studied the different state policies of transitional justice and its implications as consequences of episodes of excessive violence and regime change. “Top-down” transitional perspectives reveal divergent state approaches. Some countries provide comprehensive safeguards for ethno-religious minorities and opt for power-sharing systems, while others erase ethnic markers by imposing color-blind ideologies (Gilbert Reference Gilbert2013; Vandeginste Reference Vandeginste2014b; Russell and Carter Reference Russell and Carter2019; Yimenu Reference Yimenu2022). In general, the literature consistently indicates that avoiding open discussion about race and ethnicity after episodes of state repression allows politically and economically dominant groups to maintain their dominance rather than promote social inclusivity (Buckley-Zistel Reference Buckley-Zistel2006; Vandeginste Reference Vandeginste2014a; Kundakbayeva and Kassymova Reference Kundakbayeva and Kassymova2016; Richter Reference Richter2020).
In contrast, several papers have examined ’bottom-up’ transitional perspectives, particularly through practices of memorialization and resistance against the denial of genocide, including marching and oral transmission (Kasbarian Reference Kasbarian2018; Malinova Reference Malinova2021; Ljubojević Reference Ljubojević2022; Luitjens and Schoorel Reference Luitjens and Esther2022). In this regard, the literature has emphasized the importance of social media in transnational contexts, which help ethnic minorities to both form alliances (Axel Reference Axel2008; Biner Reference Biner2011; Koinova Reference Koinova2018; Reference Koinova2019) and make genocides visible both nationally and internationally (Walton Reference Walton2015; Tenove Reference Tenove2019).
Endogenous relationships
The remaining articles within the screened literature analyze more complex relationships between repression, activism, violence, and economic inequalities. Rather than focusing on unidirectional relationships, these papers emphasize intricate and bidirectional interactions among some of these four factors. In that sense, this last sub-section synthesizes the literature findings on the endogenous relationship between ethnic activism and state repression.
Certain scholars argue that ethnic activism can become both a cause and a consequence of ethnic-religious repression (McDoom Reference McDoom2014; Rozenas Reference Rozenas2020; Tezcür Reference Tezcür2016). These intertwined patterns are often derived from two key variables: violence and economic inequalities. When ethnic movements are illegalized or perceive an increase in government’s repression levels, they tend to resort to violence, subsequently triggering more severe repressive measures from the state (Lindemann and Wimmer Reference Lindemann and Wimmer2018). Similar effects of economic inequalities grievances were observed, leading to the emergence of ethnic subversive movements, that prompt preventive repressive actions from the state (Hasmath Reference Hasmath2019; Ye and Han Reference Ye and Han2019).
As is deduced from the literature, in certain scenarios, ethno-religious militant groups enhance their tactical capabilities to inflict more harm and evade state persecution as repression increases. As a result, repressive measures can have unexpectedly double-edged effects, increasing the challenges faced by the incumbent government as ethnic organizations and militias diversify their tactics (Horowitz, Perkoski, and Potter Reference Horowitz, Perkoski and Philip2018).
Conclusions and further areas of research
This systematic review comprehensively analyzes selected articles within SSCI from the WoS database, focusing on state repression against ethno-religious minorities. To the best of our knowledge, this is the first systematic review to address the causes, consequences, and endogenous relationships of all scopes of state repression against ethno-religious minorities in non-democratic regimes, employing PRISMA flow methodology. The aim was to organize empirical findings within this growing subfield and identify potential areas for future research.
Methodologically, our review predominantly encompasses both comparative studies among different countries and case studies of state repression against one specific ethno-religious minority. However, investigations comparing state repression against different ethno-religious minorities within the same state were notably absent. Therefore, further research is needed to explore if states uniformly repress their domestic ethno-religious minorities, and if not, what variables influence this differential repression.
Our review identified socio-demographic variables, economic and political junctures, and the role of ethnic activism as drivers of repressive measures against ethno-religious minorities. Additionally, some scholars suggest that while dehumanizing narratives and propaganda are not strictly necessary for the onset of state repression, they often aggravate the problem. Regarding consequences, the literature revealed individual effects (physical and psychological harms), group effects (identity transformation and political behavior of groups) and systemic effects (notably, impacts on transitional justice policies or perpetuation of the dominant group). Finally, some papers reported an endogenous relationship between ethnic activism and repression. Despite inconsistent findings on economic inequalities as causes of repression, a significant gap was noted: no studies explored economic inequalities resulting from state repression against ethno-religious minorities. Therefore, further research may clarify if economic ethnic inequalities are an effect of repression, or if they were concurrent or prior to state violent practices.
Bulutgil (Reference Bulutgil2018) has identified the need for understanding why states decide to repress or not different ethno-religious minorities. In one of our reviewed papers, Rozenas (Reference Rozenas2020) proposed a rational choice model to explain these phenomena. However, more empirical comparative research is needed to fully grasp this issue. Additionally, while a recent research note addressed transnational repression of ethno-religious minorities (Dukalskis et al. Reference Dukalskis, Furstenberg, Gorokhovskaia, Heathershaw, Lemon and Schenkkan2022), the lack of articles addressing this issue indicates a significant research gap that requires further investigation.
Beyond these findings, our systematic literature review has certain limitations. First, relying solely on the Web of Science database may have restricted our scope to highly cited journals, potentially overlooking relevant studies in regional or less prominent publications. Second, while we used three distinct search codes, alternative search strategies or additional databases could yield further insights. Third, our study intentionally focused on state repression of ethno-religious minorities in non-democratic countries, excluding comparisons with democratic regimes or examinations of repression against other groups, such as the LGBTIQ+ community, refugees, or migrants. While this focus aligns with our objectives, it narrows the broader understanding of repression dynamics. Finally, by centering on post-1990 trends, we excluded historical contexts that could highlight the evolution of state repression. Future reviews could address these limitations by adopting more inclusive approaches and exploring intersectional dimensions of repression.
Supplementary material
The supplementary material for this article can be found at http://doi.org/10.1017/nps.2025.19.
Disclosure
None.