From ancient times to the early 20th century, African societies engaged in indigenous slavery through methods such as warfare, raiding, and tribute. Slaves were transported via major trade routes like the Trans-Saharan, connecting regions from southwestern Ethiopia to Egypt and from central Africa to the Atlantic coast. In these societies, slaves were used for domestic work, agriculture, trade, military roles, and administrative tasks. Female slaves were often more valued, and slaves could be integrated into kinship structures with rights such as marriage and manumission.

Before the Trans-Atlantic slave trade, African slaves were exported through the Trans-Saharan, Red Sea, and Indian Ocean trades. The Trans-Saharan trade (8th to late 16th centuries) involved North African Arabs and Berbers exchanging slaves for goods. The Red Sea trade, significant in the 19th century, involved Ethiopian and Nubian slaves. The Indian Ocean trade, growing in the late 18th and early 19th centuries due to French plantations, saw slaves from the Zambezi valley and Mozambique.

The Trans-Atlantic slave trade began after Columbus’s 1492 discovery of America, peaking from the 16th to mid-19th centuries. European nations established plantations in the Americas, increasing demand for African slaves due to the death of Native Americans from disease and violence. The Portuguese first transported African slaves in 1532, with other European nations joining in the 1630s. The trade evolved through phases: the piratic trade (15th to late 16th century), monopolistic trade (1580s to late 17th century), and triangular trade (late 17th century onwards), culminating in the free trade phase (late 17th century).

The Abolitionist Movement in Europe led to the decline of the Trans-Atlantic slave trade, driven by growing concerns over its morality and brutality. Despite initial governmental resistance, economic factors tied to the Industrial Revolution made the slave trade unprofitable. European countries began outlawing the trade from 1803 to 1818, with Britain taking significant action to enforce laws. However, slavery continued in Africa until the early 20th century, with bans implemented in various colonies over time.

The Trans-Atlantic slave trade, with nearly 18 million slaves shipped, including 12 million across the Atlantic, had severe consequences. It led to the extermination of some groups, displacement, family disruption, and economic decline. While some states like Dahomey and Ashante benefited and saw the rise of new merchant classes, the trade drained Africa’s manpower and hindered local development. The constant conflict also strengthened African military organization and tribal confederations.