Slaves were shipped from Africa. The Atlantic slave trade was a major forced migration of people during which around 12.5 million people from Africa were transported to the Americas over a period of approximately 350 years. The trade developed after the need for enslaved labor rose in the late 15th century in the exploitation of the New World's resources, such as the Caribbean and the Americas. Transatlantic slave ships made repeated voyages, usually from ports in Western Europe, to West African ports where people were purchased or kidnapped, then carried across the Atlantic to the Caribbean and the Americas. From there, the slaves were distributed throughout the Americas, mainly in colonial Brazil and the West Indies and later to the Southern United States.