PortCities London

London and the transatlantic slave trade

18th-century peak

The 'asiento' and the South Sea Company

Coat of Arms of the South Sea Company.
View full size imageCoat of arms of the South Sea Company. © NMM
In 1713, when the Treaty of Utrecht was drawn up to end the War of the Spanish Succession, Britain gained the 'asiento'. The 'asiento' was the much-prized right to carry enslaved Africans to the Spanish Americas. 

The British government sold this privilege to the South Sea Company (SSC) for £7.5 million - an enormous sum. But the SSC suffered the same problems of illegal 'interlopers' as the other chartered companies. More conflict with Spain interrupted the SSC’s slave trading.

The 'South Sea Bubble'

Share certificate of the South Sea Company.
View full size imageShare certificate of the South Sea Company. © NMM
In 1720, massive speculation in the company’s shares produced the 'South Sea Bubble'. This ruined many investors when the share price crashed. 

One successful investor in SSC stock was the London bookseller Thomas Guy. He sold his shares as the price reached its peak and used his massive fortune to establish Guy’s Hospital for 'the poorest and sickest of the poor' in London. 

The SSC survived these trials and was responsible for the transportation of around 64,000 enslaved Africans between 1715 and 1731.

London at the centre of the trade

Shipping in the Pool of London.
View full size imageShipping in the Pool of London. The port dominated by the slave trade until the early 18th century. © NMM

In the first third of the 18th century, Britain’s involvement in the slave trade grew enormously. In the 1710s and 1720s, nearly 200,000 enslaved Africans were transported across the Atlantic in British ships. 

London remained the largest slaving port in Britain with perhaps more than 50 ships a year leaving for West Africa.

One of the greatest of London’s traders was Humphrey Morice of Mincing Lane. Morice was an MP and also governor of the Bank of England between 1727 and 1728. Morice was interested in the health of both his crews and the cargo of captured Africans:

  • surgeons were often carried on board his ships
  • he advocated the use of limejuice to prevent scurvy.

London eclipsed

In the 1730s, Bristol overtook London as the main slaving port. London was further eclipsed by Liverpool, which rose rapidly to dominate the British trade. 

London ships continued to carry enslaved people until the end of the trade. The city remained the main centre for financing slavery, insuring vessels and arranging cargoes for Africa.

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