Slave ships were large cargo ship

Cargo ship

A cargo ship or freighter is any sort of ship or vessel that carries cargo, goods, and materials from one port to another. Thousands of cargo carriers ply the world's seas and oceans each year; they handle the bulk of international trade...

s specially converted for the purpose of transporting slaves

Slavery

Slavery is a system under which people are treated as property to be bought and sold, and are forced to work. Slaves can be held against their will from the time of their capture, purchase or birth, and deprived of the right to leave, to refuse to work, or to demand compensation...

, especially newly purchased Africa

Africa

Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...

n slaves to Americas

Americas

The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...

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The most significant routes of the slave ships led from the north-western and western coasts of Africa to South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 and the south-east coast of what is today the USA

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

, and the Caribbean

Caribbean

The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...

. As many as 20 million Africans were transported by ship. The transportation of slaves from Africa to America was known as the Middle Passage

Middle Passage

The Middle Passage was the stage of the triangular trade in which millions of people from Africa were shipped to the New World, as part of the Atlantic slave trade...

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The African slave trade

African slave trade

Systems of servitude and slavery were common in many parts of Africa, as they were in much of the ancient world. In some African societies, the enslaved people were also indentured servants and fully integrated; in others, they were treated much worse...

 was outlawed in 1807, by a law passed jointly in the United States of America and the United Kingdom

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

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