Tree crops have changed land tenure in Africa. Planters have acquired more permanent, alienable rights, but have also faced disputes with competing claimants and the state. I show that the introduction of Para rubber had similar effects in the Benin region of colonial Nigeria. Planters initially...

I test Bates' view that trade across ecological divides promoted the development of states in pre-colonial Africa. My main result is that sub-Saharan societies in ecologically diverse environments had more centralized pre-colonial states. I use spatial variation in rainfall to control for...

African societies exported more slaves in colder years. Lower temperatures reduced mortality and raised agricultural yields, lowering slave supply costs. Our results help explain African participation in the slave trade, which predicts adverse outcomes today. We use an annual panel of African...

African societies exported more slaves in colder years. Lower temperatures reduced mortality and raised agricultural yields, lowering the cost of supplying slaves. Our results help explain African participation in the slave trade, which is associated with adverse outcomes today. We merge annual...

Motivated by a simple model, I use DHS data to test nine hypotheses about the prevalence and decline of African polygamy. First, greater female involvement in agriculture does not increase polygamy. Second, past inequality better predicts polygamy today than does current inequality. Third, the...

I show how abundant land and scarce labor shaped African institutions before colonial rule. I present a model in which exogenous land quality and endogenously evolving population determine the existence of land rights, slavery, and polygyny. I use cross-sectional data on pre-colonial African...

The ``land abundance'' view of African history uses sparse population to explain economic institutions. I provide supporting evidence from the Egba of Nigeria. I use early colonial court records to show that Egba institutions fit the theory's predictions. Before 1914, the Egba had poorly defined...

In this review, I discuss the role of African institutions in general and pre-colonial institutions in particular in explaining present-day African poverty. Six of the most often cited explanations of African poverty -- geography, ethnolinguistic fractionalization, the slave trades, colonial...