Who resisted and campaigned for abolition?

Thomas Clarkson campaigner for abolition

Leading anti-slavery activist

Thomas Clarkson was a leading activist in Britain against the transatlantic slave trade. He helped found the Committee for the Abolition of the Slave Trade and was a main force in bringing about the Slave Trade Act of 1807, which legally ended British trade in enslaved Africans.

Clarkson was born in Wisbech, Cambridgeshire, England in 1760. He was educated at Wisbech Grammar School, St Paul's School, London and St John's College, Cambridge. He was later ordained as a deacon.

In 1785, Cambridge University held an essay competition on the subject 'Is it right to make men slaves against their wills?'. Clarkson had not previously thought about slavery, but did considerable research and submitted his essay. He won first prize. On his way home to London he had what he described as a spiritual experience, later recounting how he had:

'A direct revelation from God ordering me to devote my life to abolishing the trade'.

Clarkson contacted Granville Sharp, a known anti-slavery campaigner. In 1787 they formed the Committee for the Abolition of the Slave Trade. Of the 12 committee members, nine were Quakers. Influential people such as the Methodist preacher John Wesley and pottery business man Josiah Wedgwood gave their support to the campaign. They later persuaded William Wilberforce, MP for Hull, to be their spokesman in the House of Commons.

Evidence of inhumanity of slavery

Thomas Clarkson was responsible for collecting information to support the abolition of the transatlantic slave trade. This included interviewing 20,000 sailors and obtaining equipment used on slaving ships such as iron handcuffs, leg shackles, thumb screws, instruments for forcing open enslaved Africans' jaws and branding irons. In 1787 he published his pamphlet, 'A Summary View of the Slave Trade and of the Probable Consequences of its Abolition'.

Lectures in Manchester

Clarkson travelled to Liverpool to interview sailors, where he risked his life on the dockside when he was threatened by pro-slavery supporters. He received a much warmer welcome in Manchester with its strong anti-slavery sentiments when he preached in the city's Collegiate church (which later became Manchester Cathedral) in 1787.

Clarkson later recalled the experience of delivering his hastily prepared sermon in ‘The History of the Rise, Progress and Accomplishment of the Abolition of the African Slave Trade by the British Parliament’, 1808:


‘When I went into the church it was so full that I could scarcely get to my place; for notice had been publicly given, though I knew nothing of it, that such a discourse would be delivered. I was surprised also to find a great crowd of black people standing round the pulpit. There might be forty or fifty of them. The text that I took, as the best to be found in such a hurry, was the following: Thou shalt not oppress a stranger, for ye know the heart of a stranger, seeing ye were strangers in the land of Egypt’.

There was clearly a not insignificant black population in Manchester and the north west at the time. Clarkson argued that slavery violated the most fundamental principles of Christianity and that there could be no moral justification for forcibly removing human beings from their homes and transporting them to foreign countries where they became the possessions of other men. He informed the congregation: 

‘It is a melancholy fact, but it can be abundantly proved, that great numbers of the unfortunate strangers, who are carried from Africa to our colonies, are fraudulently and forcibly taken from their native soil. To descant but upon a single instance of the kind must be productive of pain to the ear of sensibility and freedom. Consider the sensations of the person, who is thus carried off by the ruffians, who have been lurking to intercept him. Separated from everything which he esteems in life, without the possibility even of bidding his friends adieu, behold him overwhelmed in tears – wringing his hands in despair – looking backwards upon the spot where all his hopes and wishes lay... If this instance, then, is sufficiently melancholy of itself, and is at all an act of oppression, how complicated will our guilt appear, who are the means of snatching away thousands annually in the same manner, and who force them and their families into the same unhappy situation, without either remorse or shame!’

The conclusion for Clarkson was self-evident:

‘If, then, we oppress the stranger, as I have shown, and if, by a knowledge of his heart, we find that he is a person of the same passions and feelings as ourselves, we are certainly breaking, by means of the prosecution of the slave-trade, that fundamental principle of Christianity, which says, that we shall not do that unto another, which we wish should not be done unto ourselves, and, I fear, cutting ourselves off from all expectation of the Divine blessing. For how inconsistent is our conduct! We come into the temple of God; we fall prostrate before him; we pray to him, that he will have mercy upon us. But how shall he have mercy upon us, who have had no mercy upon others! We pray to him, again, that he will deliver us from evil. But how shall he deliver us from evil, who are daily invading the right of the injured African, and heaping misery on his head!’ 

Dedication to the cause

Clarkson travelled all over Britain collecting evidence and campaigning against slavery and suffered a breakdown from physical exhaustion as a result in 1793.

After the passing of the Abolition of the Slave Trade Act in 1807, he published 'The History of the Abolition of the African Slave Trade'. He joined with Thomas Fowell Buxton to form the Society for the Mitigation and Gradual Abolition of Slavery to try and eradicate slavery completely. However, it was not until 1833 that parliament passed the Slavery Abolition Act, which gave all enslaved Africans in the British Empire their freedom.

Clarkson devoted his life to the abolitionist cause, he was the driving force collecting evidence, pamphleteering, speaking and raising funds. He lobbied for the abolition of slavery for almost 50 years alongside William Wilberforce, but it is Wilberforce who gets most credit for the abolition of slavery not Clarkson. Clarkson inspired and led others, and Samuel Taylor Coleridge described him as the campaign’s ‘moral steam-engine’.

Thomas Clarkson retired to Ipswich, Suffolk, where he died on 26 September 1846.

You can listen to an actor paying the part of Clarkson in the interactive video drama This Accursed Thing /video-drama.html.

For more information on Clarkson see Ellen Gibson Wilson 'Thomas Clarkson: A Biography', 1989; www.thomasclarkson.org/; www.spartacus.schoolnet.co.uk/REclarkson.htm; www.brycchancarey.com/abolition/clarkson.htm; www.bbc.co.uk/history/historic_figures/clarkson_thomas.shtml.