Does the experience of war increase people’s religiosity? Much evidence supports the idea that particular religious beliefs and ritual forms can galvanize social solidarity and motivate in-group cooperation, thus facilitating a wide range of cooperative behaviours including—but not limited to—peaceful resistance and collective aggression. However, little work has focused on whether violent conflict, in turn, might fuel greater religious participation. Here, we analyse survey data from 1,709 individuals in three post-conflict societies—Uganda, Sierra Leone and Tajikistan. The nature of these conflicts allows us to infer, and statistically verify, that individuals were quasirandomly afflicted with different intensities of war experience—thus potentially providing a natural experiment. We then show that those with greater exposure to these wars were more likely to participate in Christian or Muslim religious groups and rituals, even several years after the conflict. The results are robust to a wide range of control variables and statistical checks and hold even when we compare only individuals from the same communities, ethnic groups and religions.

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B.P. was supported by the Cultural Evolution of Religion Research Consortium which is funded by SSHRC and the John Templeton Foundation during the initial preparation of this manuscript. J.H. thanks CIFAR. M.B. and J.C. thank the Czech Science Foundation. A.C. acknowledges a grant from Title VIII/Department of State, Bureau of Intelligence and Research for fieldwork in Tajikistan and funding from the University of San Francisco for fieldwork in Sierra Leone. The funders had no role in the study design, data collection and analysis, decision to publish or preparation of the manuscript.

Author information


  1. Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, USA

    • Joseph Henrich
  2. Canadian Institute for Advanced Research, Toronto, Ontario, Canada

    • Joseph Henrich
  3. Institute of Economic Studies, Faculty of Social Sciences, Charles University, Prague, Czech Republic

    • Michal Bauer
    •  & Julie Chytilová
  4. CERGE-EI, a joint workplace of Charles University and the Economics Institute of the Academy of Sciences of the Czech Republic, Prague, Czech Republic

    • Michal Bauer
    •  & Julie Chytilová
  5. Department of Economics, University of San Francisco, San Francisco, CA, USA

    • Alessandra Cassar
  6. Department of Human Behavior, Ecology, and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany

    • Benjamin Grant Purzycki


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M.B., J.C. and J.H. conceived the study and initiated manuscript preparation. M.B., A.C. and J.C. collected data (M.B. acknowledges N. Fiala and I. Levely as collaborators in the Ugandan project, A.C. acknowledges P. Grosjean and S. Whitt as collaborators in the Tajik project). M.B., J.C. and B.P. conducted analysis. M.B., A.C., J.C., J.H. and B.P. contributed to preparation of the manuscript, J.H. and B.P. had a lead role.

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The authors declare no competing interests.

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Correspondence to Joseph Henrich.

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