The 1400s were a pivotal time in the history of Africans. The Songhai Empire rose to prominence and new city-states arose in Hausaland, Yorubaland and Benin. One of the most significant developments, however, was European and Asian exploration of the continent and the rapid expansion of the slave trade. By the end of the century, African slaves could be found from India to the Indies, and the foundation was laid for a peculiar institution that...