# State formation across cultures and the role of grain, intensive agriculture, taxation and writing

## TL;DR

This study finds that grain cultivation, not just agriculture, likely drove the formation of large human societies and enabled taxation and writing.

## Contribution

The study uses a global phylogenetic analysis of 868 cultures to test theories about state formation.

## Key findings

- Grain cultivation most likely preceded state formation.
- Taxation emerged after grain cultivation.
- Writing more likely developed in societies that raised taxes.

## Abstract

The invention of agriculture is widely thought to have spurred the emergence of large-scale human societies. It has since been argued that only intensive agriculture can provide enough surplus for emerging states. Others have proposed it was the taxation potential of cereal grains that enabled the formation of states, making writing a critical development for recording those taxes. Here we test these hypotheses by mapping trait data from 868 cultures worldwide onto a language tree representing the relationships between cultures globally. Bayesian phylogenetic analyses indicate that intensive agriculture was as likely the result of state formation as its cause. By contrast, grain cultivation most likely preceded state formation. Grain cultivation also predicted the subsequent emergence of taxation. Writing, although not lost once states were formed, more likely emerged in tax-raising societies, consistent with the proposal that it was adopted to record those taxes. Although consistent with theory, a causal interpretation of the associations we identify is limited by the assumptions of our phylogenetic model, and several of the results are less reliable owing to the small sample size of some of the cross-cultural data we use.

Opie and Atkinson conduct a global phylogenetic analysis of 868 cultures and find evidence indicating that cereal grain cultivation, not agricultural surplus, drove state formation. Their findings also link taxation and writing to state emergence.