View of the Elmina slave castle on the north-west side featuring Dutch flag, located on the gold coast of Guinea (present day Ghana), Atlas Blaeu van der Hem, ca. 1665-1668. The Portuguese began to construct Elmina Castle in 1482. This outpost would later become a major port of embarkation in the trans-Atlantic slave trade to non-Iberian colonies in the Americas. The Dutch seized control of the castle in 1637, and continued slave trading from this site until 1814. 

While most of Western Europe did not practice slavery on a large scale in the centuries prior to the trans-Atlantic trade, Iberia’s historic ties to the ancient Mediterranean and North African slave trade provided the social and legal framework to use slavery as a major source of labor for the growing Spanish and Portuguese Empires. Iberian attitudes towards slavery prior to the sixteenth century were also very different from those that would later develop in profit-oriented, American plantation colonies. The trans-Atlantic slave trade from Portuguese outposts in western Africa to Spanish colonies in the Americas was in many ways an extension of prior slaving practices in Iberia, and the documented exchanges between Iberian traders, politicians, and religious leaders during the early years of New World expansion provide invaluable insights into the earliest stages of how the enslavement of sub-Saharan Africans became a legitimized, state-supported institution in the Americas. 

Lithographic plate showing harvesting of sugarcane on a Trinidad sugar plantation, created by Richard Bridgens, 1836. Columbus first encountered Trinidad in 1498, and the island remained in Spanish hands (despite a significant number of French settlers) until 1797, when it became a British colony.  

Spain’s use of enslaved sub-Saharan Africans in its early Caribbean colonies set a precedent that was soon followed by other European powers, and beginning in the late 1600s, non-Iberian colonies developed forms of plantation slavery that would come to dominate much of the tropical Americas until the nineteenth century. Rather than directly copying Iberian attitudes towards slavery and Iberian forms of slave labor, northern European colonization of places such as the English colony of Barbados represented a modification of Iberian traditions. Arguably, however, the body of European laws and customs that developed in support of the slave trade, and the widespread practice of enslaving Amerindians and Africans as a significant labor force in the Americas, were ultimately rooted in processes of Iberian expansion that unfolded during the fifteenth and sixteenth centuries.

Portrait of an African Man, painting by Jan Mostaert, ca. 1525-1520, courtesy of Rijksmuseum Amsterdam. Painting demonstrates Atlantic Creole influences in the sixteenth century Atlantic World, and the clothing worn by the subject of the portrait point to Spanish-Portuguese origins or influences. The painting also suggests that early depictions of Africans by Europeans were not necessarily derogatory, though this began to change with the increase of rigid racial hierarchies to support slavery during European colonization of the Americas.

These documents written at the dawn of the sixteenth century show how Iberian administrators and colonists rapidly came to rely on enslaved sub-Saharan Africans as a means of supporting large agricultural and mining enterprises in the Americas. Just twenty-five years after enslaved Africans were first transported from Spain to the island of Hispaniola, Iberians would launch the trans-Atlantic slave trade from Africa directly to the Caribbean.

This led to a system of forced migration that uprooted and transformed the lives of an estimated twelve million sub-Saharan Africans by the end of the nineteenth century. However, rather than viewing slavery in the Iberian world as the direct root of rigid racial hierarchies and vast social inequalities enforced by European colonial powers all over the Americas during the colonial era, it should be remembered that in late medieval and early modern Iberia, slavery was not associated with people of any particular racial category or ethnic background. At the same time that Portuguese expansion and overseas commerce increasingly facilitated the export of captives from western Africa, the Spanish Crown’s emphasis on limiting the spread of Islam ensured that enslaved laborers sent to the Americas would be sub-Saharan Africans, rather than Iberian moriscos, or Muslims from Eastern Europe and the Mediterranean world. Other factors—most importantly the decimation of Amerindian populations in much of the Caribbean—also played a key role in determining that in the Spanish Americas after the 1540s, only sub-Saharan Africans would be enslaved. Ultimately, the connection between slavery and race did not fully develop into a rigid racial hierarchy until European colonization of the Americas.