This research examines the economic origins and spread of Islam in the Old World and uncovers two empirical regularities. First, Muslim countries and ethnic groups exhibit highly unequal regional agricultural endowments. Second, Muslim adherence is systematically higher along the pre-Islamic...

This study explores the consequences and origins of contemporary differences in well-being across ethnic groups within countries. We construct measures of ethnic inequality combining ethnolinguistic maps on the spatial distribution of groups with satellite images of light density at night....