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...