The Atlantic slave trade was the sale and exploitation of African slaves by Europeans that occurred in and around the Atlantic ocean from the 15th century to the 19th century. Most slaves were transported from West Africa and Central Africa to the New World.

Historians estimate that 12 million Africans arrived in the New World, making it one of the largest forced migrations in human history. However some estimate that the number is as high as 25 to 40 million. The slave-trade is sometimes called the Maafa by African and African-American scholars, meaning holocaust or great disaster in Kiswahili. The slaves were one element of a three-part economic cycle: the Triangular Trade...

The first side of the triangle was the export of goods from Europe to Africa. A number of African kings and merchants took part in the trading of slaves from 1440 to about 1900. For each captive, the African rulers would receive a variety of goods from Europe. Many of them were confronted with the dilemma of trading with Europe or becoming slaves themselves.

Five times the number of slaves were transported to the Americas compared to those transports to Europe. This is because the slaves were exposed to new diseases and also because of malnutrition. The third and final part of the triangle was the return of goods to Europe from the Americas. The goods were the products of slave-labor plantations and included cotton, sugar, tobacco, molasses and rum.

European colonists enslaved many of the natives of the New World but for a variety of reasons Africans replaced American Indians as the main population of slaves in the Americas. In some cases, such as on some of the Caribbean Islands, disease and warfare eliminated the natives completely.

Research published in 2006 reports the earliest known presence of African slaves in the New World: a burial ground in Campeche, Mexico suggests slaves had been brought there not long after Hernán Cortez completed the subjugation of Aztec and Mayan Mexico.

In Britain, the U.S. and in parts of Europe, moral, economic and political opposition developed against the slave trade. This was, however, largely ineffective unless combined with the political factor of African rebellions. The single most significant event in the history of the abolition of the Atlantic slave trade and slavery was the Haitian Revolution (1791-1804) led by Toussaint L'Ouverture and Jean-Jacques Dessalines. Prior to the Haitian Revolution there were no major reversals in the centuries-old trend of an increasing trade in Africans across the Atlantic.

After the Haitian Revolution, there was an immediate and terminal decline. This is because the Haitian Revolution and other uprisings created such significant military and political fears and costs for the European/American colonial powers outweighed stability and profitability.

In Great Britain, led by the Religious Society of Friends (Quakers) and establishment Evangelicals such as William Wilberforce, the Abolitionist movement began to protest against the trade but until the Haitian Revolution they were successfully opposed by the owners of the colonial holdings. Denmark, which had been very active in the slave trade, was the first country to ban the trade through legislation in 1792 - one year after the start of the victorious insurrection in Saint-Domingue (modern day Haiti).

Denmark's legislation only took effect in 1803, as the Haitian Revolution moved towards its final victory. Britain banned the slave trade in 1807, imposing stiff fines for any slave found aboard a British ship. The Royal Navy, which then controlled the world's seas, moved to stop other nations from filling Britain's place in the slave trade and declared that slaving was equal to piracy and was punishable by death.