1500s

Spanish Crown authorization in 1501 permitted enslaved Africans born in Spain to be transported to Hispaniola. This marked the formal beginning of African slavery in the Americas. The Spanish explicitly preferred Africans who had been baptized and raised in Iberia, fearing direct imports from Africa would introduce people with no Christian acculturation. Within decades the policy would be reversed as demand for labor far outstripped supply of 'ladino' slaves.

By the mid-sixteenth century the Triangular Trade had become the defining economic system of the Atlantic world: European manufactured goods traveled to West Africa to purchase enslaved people; enslaved Africans were transported across the Middle Passage to the Americas; American commodities produced by enslaved labor (sugar, tobacco, cotton, rice, indigo) were shipped to Europe. This system generated massive capital accumulation in Portugal, Spain, England, France, and the Netherlands, financing early modern European economic development while destroying millions of African lives and futures.

Scholarly analysis of early Atlantic slave voyages indicates that mortality during the Middle Passage in the early sixteenth century ranged from roughly 15 to 25 percent of captives per voyage, driven by dysentery, dehydration, scurvy, smallpox, and the brutal conditions of confinement. Enslaved people were chained in spaces as small as 18 inches high for voyages lasting six to fourteen weeks. Those who died were thrown overboard. These death rates declined somewhat in later centuries as traders sought to protect their 'investment,' but remained catastrophically high throughout the trade's history.

Holy Roman Emperor Charles V (King of Spain) granted the first formal asiento — an exclusive contract — authorizing the direct shipment of 4,000 enslaved Africans annually to the Spanish Caribbean colonies, bypassing the previous requirement that enslaved people be 'seasoned' in Spain first. This bureaucratic innovation massively accelerated the slave trade and established the asiento system that would govern the trade for over two centuries, later fought over by European powers as a source of enormous profit.

On December 26, 1522, approximately twenty enslaved Wolof Africans on the sugar plantation of Diego Columbus (son of Christopher Columbus) in Hispaniola rose in revolt, killing several Spaniards and attempting to ignite a broader uprising. The revolt was suppressed and the leaders executed. It is recognized as the first major slave revolt in the Americas. Spanish authorities responded by restricting the import of Wolof captives, whom they labeled as 'proud and disobedient,' but demand for labor prevented meaningful curtailment of the trade.

King Afonso I of the Kongo Kingdom (in present-day Angola and Congo) wrote a series of letters to King João III of Portugal in 1526, explicitly protesting the devastating effects of the slave trade on his kingdom. He described how Portuguese and African traders were kidnapping nobles, free people, and even children of noble families. He demanded Portugal stop the trade or strictly regulate it. His letters represent one of the most detailed and powerful contemporary African denunciations of the Atlantic slave trade. Portugal ignored his appeals. The Kongo Kingdom's population and political stability were steadily destroyed by the trade over the following centuries.

In 1532, enslaved Wolof Africans aboard a Portuguese slave vessel revolted during the Middle Passage, making this the first documented slave ship revolt in the Atlantic. The uprising was suppressed. Ship revolts were a persistent form of resistance throughout the trade's history — scholars estimate revolts occurred on approximately one in ten slaving voyages, forcing traders to invest heavily in chains, armed guards, and netting. The ever-present threat of revolt shaped the brutal architecture of the slave ship.

Emperor Charles V issued the New Laws of the Indies in 1542, responding to Dominican friar Bartolomé de las Casas's advocacy on behalf of indigenous peoples. While the laws nominally prohibited indigenous enslavement and the encomienda system, they explicitly excluded Africans from protection and thus accelerated the substitution of African enslaved labor for indigenous labor throughout Spanish America. Las Casas himself had earlier suggested importing Africans as a solution to indigenous suffering — a position he later deeply regretted. The New Laws represent a pivotal moment when European law racially differentiated human enslavement.

English sea captain John Hawkins launched England's entry into the Atlantic slave trade in 1562, seizing approximately 300 Africans from Sierra Leone and selling them in Hispaniola. Queen Elizabeth I initially protested but later invested in and knighted Hawkins after his profitable second voyage in 1564. His voyages established the English pattern of violent seizure and commercial sale of enslaved Africans, laying groundwork for England's eventual dominance of the trade in the seventeenth and eighteenth centuries. England would transport more enslaved Africans than any other nation.

The Moroccan Sa'adian sultan Ahmad al-Mansur invaded the Songhai Empire and destroyed it at the Battle of Tondibi in 1591. The collapse of the last great Sahelian empire shattered the political order of West Africa, creating warfare, instability, and displacement that slave traders and their African collaborators systematically exploited to capture and sell millions of people over the following century. Historians regard the Songhai collapse as a major accelerant of the Atlantic slave trade's expansion.

Following the Spanish settlement of Cuba, enslaved Africans were transported to the island beginning around 1513 to labor in gold mining and agricultural production. The Spanish government issued licenses (asientos) controlling the trade. Cuba's plantation economy would eventually make it one of the largest recipients of enslaved Africans in the entire Atlantic trade, with over 800,000 people imported over the following centuries.

In 1533 enslaved Africans and remaining Taíno indigenous people in Cuba staged a joint revolt against Spanish colonizers in the gold mining regions. The uprising was suppressed by Spanish military force and its leaders were killed. The alliance between African and indigenous resistance fighters illustrated both the shared experience of colonial exploitation and the potential for cross-ethnic solidarity that Spanish authorities worked deliberately to undermine in subsequent decades.

Hernán Cortés brought enslaved Africans with him on his conquest of Mexico beginning in 1519. Among them were both enslaved laborers and free Black participants like Juan Garrido. As the conquest proceeded and indigenous populations collapsed under disease and violence, demand for enslaved African labor in New Spain (Mexico) rapidly grew. Mexico became a significant destination for the Atlantic slave trade, with an estimated 200,000 Africans imported over the colonial period.

Estevanico (also called Esteban de Dorantes), an enslaved African man from Morocco, was among the survivors of the disastrous Narváez expedition to Florida (1527). He spent eight years traversing the continent from Florida to Mexico with Álvar Núñez Cabeza de Vaca, serving as healer, interpreter, and diplomat among indigenous communities. In 1539 he led an advance expedition toward the Seven Cities of Cibola into present-day Arizona and New Mexico, becoming the first African and the first person of non-indigenous origin to reach the American Southwest. He was killed by Zuni people near Hawikuh. His story reveals both African presence in early American exploration and the inescapable fact of his enslavement.