We thank Q. Atkinson and A. Willard for feedback on an earlier version of the manuscript and E. Postma for discussions on parts of the statistical analyses. We acknowledge the contributions of our team of research assistants, post-doctoral researchers, consultants and experts. See http://www.seshatdatabank.info for a comprehensive list of private donors, partners, experts and consultants. This work was supported by an ESRC Large Grant entitled ‘Ritual, Community, and Conflict’ (REF RES-060-25-0085), a John Templeton Foundation grant to the Evolution Institute entitled ‘Axial-Age Religions and the Z-Curve of Human Egalitarianism’, a Tricoastal Foundation grant to the Evolution Institute entitled ‘The Deep Roots of the Modern World: The Cultural Evolution of Economic Growth and Political Stability’, an Advanced Grant (‘Ritual Modes: Divergent modes of ritual, social cohesion, prosociality, and conflict’, grant agreement no. 694986) and a Starter Grant (‘The Cultural Evolution & Ecology of Institutions’, grant agreement no. 716212) from the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Programme, an award from the Templeton World Charity Foundation entitled ‘Cognitive and Cultural Foundations of Religion and Morality’ (TWCF0164), a Keio Research Institute at SFC Startup Grant, a Keio Gijuku Academic Development Fund Individual Grant and a grant from the European Union Horizon 2020 Research and Innovation Programme (grant agreement no. 644055 (ALIGNED, www.aligned-project.eu)).

Reviewer information

Nature thanks Carol Ember, Peter J. Richerson and the other anonymous reviewer(s) for their contribution to the peer review of this work.