Slavery has occurred in almost every society over the years, until the last two or three hundred years, including in Nigeria https://en.m.wikipedia.org/wiki/Sl

Slavery has occurred in almost every society over the years, until the last two or three hundred years, including in Nigeria https://en.m.wikipedia.org/wiki/Slavery_in_Nigeria https://en.m.wikipedia.org/wiki/Slavery_in_Nigeria See "Black rednecks and white liberals" by thomas sowell for more info (Thomas sowell is a black american economics professor and writer, for any in the audience who decide what is worth reading based on the skin color or ethnicity of the author)