The Asiento de Negros was a monopoly contract between the Spanish Crown and various merchants for the right to provide enslaved Africans to colonies in the Spanish Americas. The Spanish Empire rarely engaged in the transatlantic slave trade directly from Africa itself, choosing instead to contract out the importation to foreign merchants from nations more prominent in that part of the world, typically Portuguese and Genoese, but later the Dutch, French, and British. The Asiento did not concern French or British Caribbean but Spanish America.

Slavery in the Spanish American viceroyalties was an economic and social institution which existed throughout the Spanish Empire including Spain itself. Enslaved Africans were brought over to the continent for their labour, indigenous people were enslaved until the 1543 laws that prohibited it.