The movement against the slave trade had deep and slowly developing roots. Was slavery legal in England? Could slaves be removed from the country against their wishes? What was to be done about the maltreatment of black people?
All these questions and more surfaced in legal battles from the mid-18th century onwards. The Somerset case of 1772 ruled that slavery was illegal in England, calling into question the right of slave owners to hold jurisdiction over slaves brought to England.
In the Zong case of 1781 the owners of a British slave ship sought compensation for the loss of cargo, when over a hundred enslaved Africans were thrown overboard.
Both these landmark cases had been backed by the theologian, Granville Sharp, who became a key member of the abolitionist movement.
Defeat in North America
With the British defeat in the war in North America in 1783 slavery was set in a different context. Slavery had been at the heart of that conflict, and many of the defeated British came home with former slaves.
The problem of the black poor
There was also the problem of the black poor in London in the mid-1780s and discussion about what to do about them. This resulted in the Sierra Leone Scheme, designed with government backing to relocate them to Africa. It proved disastrous and gave focus to the issue of slavery and the slave trade.
Boycotting slave-grown sugar
The boycott of slave-grown sugar became an important feature of the abolition campaign. Refusing to buy sugar for the home, and preventing its domestic use, emerged as a contribution by women to the campaign.
The birth of the formal abolition campaign
At the time of these events a small band led by William Wilberforce in Parliament and by Thomas Clarkson in the country as a whole, launched the formal campaign to abolish the slave trade.