The British Empire’s Role In Ending Slavery Worldwide

We hear much of the UK’s involvement in the transatlantic slave trade, but little or no mention is made of the pivotal role Britain also played in its suppression worldwide…

“The unweary, unostentatious, and inglorious crusade of England against slavery may probably be regarded as among the three or four perfectly virtuous pages comprised in the history of nations.”  William Edward Hartpole Lecky, Irish historian and political theorist.

We hear much of the UK’s involvement in the transatlantic slave trade but little or no mention is made of the pivotal role Britain also played in its suppression worldwide.

Britain’s role involved not only money and bribes, usually to pay off slave owners, slave traders and regional leaders, but also humanitarian and diplomatic pressure, and even military might.

Many other European countries were also heavily involved in the slave trade. The French, Dutch, Germans, Portuguese and Spanish also had colonies, mostly in Africa, the Caribbean and the Americas. The Portuguese were the nation most heavily involved in the trade.

In Britain, pressure from abolitionists, including such people as William Wilberforce MP, led to the Slave Trade Act of 1807 banning the trading in enslaved people in the British Empire, but not slavery itself.

Further afield, diplomacy was integral to the British fight to abolish slavery. At the Treaty of Vienna of 9th June 1815 (nine days before the Battle of Waterloo), the Foreign Secretary Viscount Castlereagh put pressure on allies France, Spain and Portugal, the main slave buying countries, to abolish their slave trade.

At Britain’s insistence, the treaty also included a clause condemning the slave trade, the first time a declaration of what we now know as human rights had appeared in an international treaty. Britain also petitioned the Pope for support.

The Anti-Slavery Society Convention, 1840, by Benjamin Robert Haydon

After sustained campaigning in Britain, the Slavery Abolition Act came into force in 1834 and finally banned slavery throughout the Empire. In order to free some 800,000 slaves, Parliament paid a huge £20m – a third of the Treasury’s annual income at the time – in compensation to the slave owners in the Caribbean, South Africa and Canada. And in 1843 Britons were forbidden to own slaves anywhere in the world.

Some states, including Spain and Portugal, agreed to end trafficking in slaves – with compensation paid by Britain.

However this was not universally popular. In Cape Colony, South Africa, the Boers, Dutch speaking settlers, trekked out of British territory, outraged at the abolition of slavery there. The decision of Britain to abolish slavery in all its colonies in 1834 meant all 35,000 slaves registered with the Cape Governor were to be freed. Many Boers were dependent on slave labour for their livelihood. Compensation was offered by the British government, but the Boers would have to travel to London for payment, and few could afford to make the trip. This final intrusion into the way the Boers lived their lives was the last straw: many Boers decided to trek eastwards, beyond the boundaries of British rule. This became known as the Great Trek (In Afrikaans: Die Groot Trek).

So many nations reneged on their promises that Britain placed a naval squadron off the coasts of East Africa, looking to intercept slave ships: the West Africa Squadron. This patrol, sometimes just a handful of ships, sometimes as many as 20, patrolled the Atlantic from 1808 to 1870, landing their human cargo at Freetown in Sierra Leone, a colony set up for freed slaves. Over 62 years the Royal Navy captured hundreds of slave ships and freed some 160,000 captives. Several hundreds of thousands more were saved by diplomatic and naval pressure.

HMS Black Joke firing on the Spanish Slaver El Almirante

This patrol was expensive both in money – a great deal of British tax payers money – and in life. Over 60 years or so patrolling the Atlantic, some 17,000 sailors died; some killed in action, some from the same diseases as the slaves they freed, including fever, dysentry, yellow fever and malaria. This represented one sailor’s life lost for every nine slaves freed.

At this time, the 1830s, the trading of palm oil was worth more than slaves and abolitionists argued that Britain should keep a presence in Africa in order to promote the legitimate, lucrative and more ethical trade in palm oil to the local tribes, rather than slaves.

However the slave trade continued and the Royal Navy turned to blockading rivers and destroying slave ‘pens’ ashore, regardless of to whom the land belonged. These ‘pens’ were places where slaves were kept and sold.

There was constant diplomatic friction between slave-owning states and Britain. British officials were often threatened with violence.

At first America and France refused to let the Royal Navy stop and search ships flying their flags. However during bad weather in the 1830s and 1840s several American ships were forced into British waters by bad weather and had their slave cargoes released.

A serious diplomatic incident occurred in 1841 when the American ship Creole was seized by the slaves it was carrying en route from Virginia to New Orleans to be sold. The slaves were given asylum in the Bahamas, ruled by Britain, where they were set free.

In Africa Britain made some 45 treaties with African rulers to stop slaving at source, however in some cases they had to be paid off. Quite often Britain was also invited to offer protection, for example Africans on the coast were being terrorised by the aggressive slave kingdom of Ashanti and requested British protection.

In 1839 the British Foreign Secretary Palmerston ordered the seizure of Portuguese slave ships and in 1845 his successor Lord Aberdeen declared Brazilian slavers as pirates and open to seizure.

In 1850 the British navy entered Brazilian ports to destroy or seize the slave ships, a decisive action in ‘persuading’ Brazil, the biggest slave buyer of them all, to end slavery.

Cross-section of a slave ship, from ‘Notices of Brazil’ in 1828 and 1829 by Robert Walsh

Cuba was supplied by American slavers, who could not be boarded by the British. However after the American Civil War, President Lincoln signed a secret treaty allowing the British to intercept American slave ships. This stopped Spanish and Cuban slave trading and effectively ended the trans Atlantic slave trade.

Slavery itself remained legal in the US until the 1860s and in Latin America until the 1880s.

Central Africa was being ravaged by Muslim slave traders supplying the Middle East. The Foreign Office estimated that in the 1860s around 30,000 people a year were being trafficked, huge numbers dying along the slave routes across the Sahara desert to the coast.

Arab slave traders and their captives, 19th-century drawing by David Livingstone.

British abolitionists were inspired to stop this monstruous trade by explorer and missionary David Livingstone. Diplomatic, discreet action was required. Thomas F. Reade, consul-general of Cairo in the 1860s, disguised himself as an Arab and infiltrated the slave markets. He estimated that around 15000 slaves were sold in Cairo every year. Other British diplomats actively helped to free slaves, including buying their freedom with official funds or organising safe houses for them.

The British campaign against slavery was not seen as just a humanitarian cause. French and American slave traders accused Britain of using it as a pretext for colonial expansion into West Africa, Cuba and even Texas. However slave trading was booming at this time and it would have been in Britain’s economic interests to continue with it. Instead the abolitionist, humanitarian and religious pressure at home won out and luckily Britain, a rich country, was able to afford to act as she did.

Britain is often condemned for not paying compensation to the enslaved as well as the slave owners. It would have been economically impossible to compensate each enslaved person individually.

Britain aimed to stop slavery not just at the time but also in the future. Its efforts to supress the slave trade worldwide became known as the ‘British Crusade’.

Published 16th April 2023

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