Infibulation – the narrowing of the vaginal opening after the removal of the clitoris and labia – is the most invasive form of female genital cutting. The extent to which it is practiced varies widely within Africa. This paper studies the economic origins of this heterogeneity by testing the anthropological theory that a particular form of pre-industrial economic production – subsisting on pastoralism – favored the adoption of this custom. The hypothesis is based on the fact that pastoralism was characterized by heightened paternity uncertainty due to frequent and often extended periods of male absence from the settlement, implying larger payoffs to controlling female sexuality. Using within-country variation across 80,000 women in 12 African countries, the paper first documents that women from historically more pastoral societies are significantly more likely to be infibulated today. Extending the analysis to a set of 500,000 individuals in 34 countries, the paper then shows that formerly pastoral societies also exhibit a broader set of customs and norms that restrict female sexuality: female descendants of pastoral societies (i) are more constrained in their mobility outside their home; (ii) hold more restrictive norms about female sexuality; and (iii) behave less promiscuously. Given that dependence on pastoralism was largely determined by ecological conditions, these relationships have a direct causal interpretation. I argue and show empirically that the mechanism behind these patterns is indeed male absenteeism, rather than . . .