The transatlantic slave trade began to flourish in the 16th century. It quickly became a major enterprise for Portuguese, British, Spanish, French, and Dutch traders.

They established posts along the African coast and allied with local leaders to capture people from the interior, often the victims of war and political conflict. European slave traders provided guns, cloth, and other manufactured goods in exchange for captives.
These enslaved men, women, and children endured the brutal “Middle Passage” across the Atlantic Ocean. They were shackled and crammed into the hold of a ship alongside hundreds of others. Crowded conditions and inadequate hygiene facilities meant that disease and malnutrition were rampant. Many did not survive the nightmarish journey. Those who did were sold at ports in North America, the Caribbean, and South America.
The shrieks of the women, and the groans of the dying, rendered the whole a scene of horror almost inconceivable.
-Olanduh Equiano's description of the middle passage, 1798