How did the transatlantic slave trade cause an increase in wars in Africa?

African elites engaged their armies in warfare with neighboring peoples. While this kind of thing happened in other parts of the world, the European demand for slave labor significantly increased warfare within Africa. For example, when the Oyo Empire of West Africa defeated their rivals in southern Yoruba states, they profited from the spoils of that victory by selling their captives into slavery. The political victory became a rewarding economic one as well, a kind of bonus thanks to the slave trade. The Oyo would not have considered this selling their "own" into perpetual (unending) torture and enslavement, for the Yoruba had been their enemy. In return for supplying slaves, African elites were paid with a variety of manufactured products including guns, cotton textiles, glass, and food products made from the very sugar grown by slaves in the Americas. This had a drastic economic and political impact in Africa, which drove so many to participate in the trade. From the European point of view, slave labor was crucial for economic production and increasing wealth. The expansion of plantation agriculture from Brazil into the Caribbean drove the expansion of the slave trade. By the end of the trade in the nineteenth century, more than eight out of every ten Africans taken in bondage to the Americas had disembarked (arrived) in either Brazil or the islands of the Caribbean. Sugar—so labor intensive and difficult to produce—ruled these regions. African laborers toiled from sunup to sunset under grueling conditions. So harsh was this labor that the average life expectancy for a slave in Brazil was only twenty-three years. The high mortality rate only led to even greater demand for enslaved people in Brazil.

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