"Us" Against "Them": Ethnicity in Conflict

Whilst war fractures societies, it can bring about reinforced bonds within the communities it targets. By analysing ethnic conflicts across 36 African countries between 2002 and 2015, economist Matteo Sestito offers an original perspective on the mechanisms that forge identities and strengthen cohesion within the communities it strikes.

With more than 5.4 million deaths, the Second Congo War, which began in 1998, is widely regarded as one of the deadliest conflicts since the Second World War. Although the Pretoria Agreement formally ended the war in 2003, the violence did not end in the Democratic Republic of the Congo (DRC): indeed in Kivu, in the country’s north-east, armed confrontations have continued for more than two decades. Such conflicts starkly illustrate the political and ethnic dimensions of organised violence. The region’s abundant mineral wealth, particularly in coltan, has fuelled intense competition. Yet Kivu is also home to multiple ethnic communities, including the Nande, Banyarwanda (Hutu and Tutsi), Nyanga, Hunde and Tembo peoples. 

Since Congo’s independence in 1960, the region has remained marked by instability and recurrent ethnic tensions, and the proliferation of armed actors and local militias has turned Kivu into a tinderbox – where violence unfolds both between and within ethnic groups1.

Identities and internal divisions

Economic research has long demonstrated that ethnic identities tend to intensify during periods of conflict, and this debate is deeply rooted in Africa’s colonial history. Border-making, colonial administration and selective support for particular communities contributed to the institutionalisation of ethnic divisions. In several colonial contexts, favouring one group over another became a strategy of governance which depended on internal fragmentation. 

The idea – perhaps counterintuitive – that war can strengthen social cohesion and ethnic identity motivates Matteo Sestito’s study of ethnic conflict and intra-group cooperation across Africa from 2002 to 2015.

Identifiying ethnic conclict

To investigate this phenomenon, Sestito faced a major methodological challenge: geolocated conflict data from the Armed Conflict Location and Event Data (ACLED) database does not identify whether a conflict is ethnic in nature. Violence can involve state forces, rebel groups, militias, or protests without necessarily being ethnic in nature; it may instead stem from territorial, religious, or political disputes.

In the absence of comprehensive data on ethnic conflict, most existing studies have focused on localised case studies. Sestito assembled a new database comprising more than 1,900 armed groups operating across 36 African states, covering approximately 60 per cent of the continent’s land area.

To identify conflicts with an ethnic dimension, the researcher cross-referenced this data with a broad range of sources, including academic literature, reports from international and non-governmental organisations, and press coverage. This allowed him to determine which groups recruited, fought, or mobilised explicitly in the name of ethnic identity.

Measuring cohesion

Such an undertaking requires careful handling, since armed groups often reflect overlapping identities. The Niger Delta Liberation Front, for example, draws on an Ijaw ethnolinguistic and cultural base, while its leadership has included members of the Urhobo community.

This database was then matched with survey data from Afrobarometer, an independent pan-African research network. These surveys capture ethnic identity through respondents’ reported mother tongue. Sestito’s sample includes approximately 150,000 individuals belonging to 448 ethnolinguistic groups across 36 African countries. Social cohesion was measured through indicators such as participation in community meetings, involvement in local associations and engagement in collective action.

An initial finding suggests that these conflicts correspond less to conventional “wars” over regime change or territorial conquest than to diverse forms of violence. They include separatist movements, such as in the Niger Delta; Tuareg and Islamist rebellions in Mali; insurgencies in Kenya; and disputes between nomadic Fulani pastoralists and sedentary farming communities across West Africa and Nigeria. In the dataset, ethnic conflicts account for approximately 5 per cent of recorded events.

Gaining awareness, from violence

Sestito’s research suggests that when people experience ethnic violence, they feel more strongly attached to their ethnic identity and are more likely to cooperate with members of their own community. Once an ethnolinguistic group is caught up in violent confrontation, people often become more conscious of “us” and pull together. Other threats can trigger similar reactions, but the effect is much stronger when violence is clearly organised along ethnic lines.

Strenghtening identity... even remotely

To test these findings, Sestito demonstrated that the effect persists even among members of targeted ethnic groups who live far from conflict zones. In other words, strengthened identity cannot be explained solely by direct exposure to violence, wartime trauma or the collapse of local institutions. It also spreads through narratives, shared affiliations and the perception of collective threat.

The study further shows that the relationship between conflict and social cohesion weakens in more heterogeneous settings where multiple ethnolinguistic groups coexist. This suggests that increased cooperation remains largely confined to the targeted group itself. By contrast, conflicts unrelated to respondents’ own ethnic group have no measurable effect on community engagement, highlighting the central role played by ethnic affiliation.

Spreading cooperation

Several mechanisms may explain these findings. Under conditions of insecurity, individuals often turn to their communities as sources of mutual support and collective protection.

Violence can lead communities to organise local self-defence groups. Over time, the habits of cooperation built within these groups may spread beyond them and shape community life more broadly. Conflict also leaves psychological scars: experiences of injustice can fuel resentment and strengthen people’s sense of solidarity with their own ethnic group.

In his article, Sestito also draws on a socio-biological interpretation of ethnocentrism. Ethnic divisions can reactivate a stark, binary worldview – one that pits the in-group against out-groups – shaped by a combination of cultural, political, social and biological factors. This framework helps explain not only hostility towards external groups, but also solidarity and cooperation within one’s own. These findings raise broader questions about how such dynamics can be mobilised politically in nationalist narratives, and they invite reflection on possible alternatives.  If conflict breaks some social ties while strengthening others around a collective “us” defined against outsiders, how can communities build cohesion without hardening ethnic divisions?

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  Rusamira, É.  (2003). La dynamique des conflits ethniques au Nord-Kivu : une réflexion prospective. Afrique contemporaine, 207(3), 147-163. https://doi.org/10.3917/afco.207.0147. (French language only).