The triangular trade
The slave trade began with Portuguese, and some Spanish, traders taking African slaves to the American colonies they had conquered in the 15th century. British sailors became involved in the trade in the 16th century, and the Treaty of Utrecht (1713) gave them the right to sell slaves in the Spanish Empire.
In the 18th century, perhaps 6 million Africans were taken to the Americas as slaves, at least a third of them in British ships.
For the British slave traders it was a three-legged journey, called the 'triangular trade':
Taking trade goods, such as guns and brandy, to Africa to exchange for slaves.
Then taking the slaves on the 'Middle Passage' across the Atlantic to…