The West African slave trade had a variety of effects on the nations in western Africa. Obviously, for one, they were being plundered of the young, able-bodied men and women who could work and grow the population, but these tended to be from smaller tribes and nations further inland. The coastal cities and tribes grew rich as they became ports of entry, creating trading establishments, and sold slaves to the traders. These cities benefited because they were oft visited, which allowed them to become vendors of many goods for the slave traders in addition to the supply of enslaved individuals.
The inner regions became more and more impoverished, but the coastal cities became more established. The effects of this are still evident today, as coastal cities are the prominent cities and capitals of West African nations like Senegal and Cote d'Ivoire.