Slavery in the United States existed in the 18th and 19th centuries. It was primarily Africans or African Americans. Slavery was practiced in America when it was still under the rule of Great Britain and it was legal in the 13 colonies. The north abolished it there after the Revolutionary War. Due to the invention of the cotton gin though, there was a greater need for more people to gather the cotton, so slavery was continued in the deep south.
At one point the southern leaders thought about annexing Cuba to use as a slave territory. This continuation of slavery in the south caused a polarization over the issue of slavery. This lead to the Civil War which ended slavery in the United States.