London played a central role in Britain's involvement in the transatlantic trade in enslaved Africans. Because London was Britain’s major port, ships owned by London merchants dominated the trade during the 17th and early 18th centuries. Later, London's position was challenged by Bristol and then Liverpool.
The City of London provided the money for many slaving voyages and other London institutions insured cargoes and traded plantation goods.
London also became the focus of the long abolition campaign. This eventually outlawed the British slave trade and slavery within the British Empire.