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Clarkson, Thomasfree

  • Hugh Brogan

Thomas Clarkson (1760–1846)

by Carl Fredrik von Breda, 1788

Clarkson, Thomas (1760–1846), slavery abolitionist, was born on 28 March 1760 in the free grammar school, Wisbech, Cambridgeshire, of which his father, the Revd John Clarkson (1710–1766), was headmaster. His mother, Anne (1735–1799), was the daughter of Alpe Ward, a well-off and well-connected physician of Royston, Hertfordshire; her mother was one of the Banyers, a leading Wisbech family of Huguenot descent with many connections in the gentry of Essex, including the naval Rowley family. John Clarkson was a Yorkshireman; his sons believed that through him they were distant cousins of the father of English abolitionism, Granville Sharp. Thomas was the eldest of three children; there was a second boy, John Clarkson (1764–1828), who was born on 4 April 1764, and a daughter, Anne; both sons were born in the grammar school. After the headmaster's death the family continued to live in Wisbech, but paid frequent visits to their Essex relations. Thanks to the Rowleys, and after completing his schooling at the grammar school, John joined the Royal Navy in 1777 as a ‘young gentleman’ in Captain Joshua Rowley's ship, HMS Monarch.


Thomas Clarkson also attended the grammar school, and in 1775 was sent to St Paul's School, London; in 1779 he was admitted as an exhibitioner to his father's college, St John's, Cambridge. He was raised to a scholarship the next year, and with these awards, or private money, was described as 'rather a gay man', keeping two horses. It is unlikely that he was really frivolous: he was a devout, assiduous soul, taking after his father, a notably conscientious parson. He seems to have had no sense of humour at all, though he liked others to be merry. Physically, he was tall and heavy, with a strong constitution. His brother John, by contrast, was small and lively, but was as strongly religious, and shared to the full his brother's strong human sympathy: he detested the navy's use of flogging as a punishment.

Thomas Clarkson graduated BA in 1783 with a solid rather than a distinguished degree in mathematics, but remained at Cambridge to prepare himself to be a clergyman. He was decidedly ambitious; after winning a university Latin essay prize in 1784 he resolved to win it again the following year. The essay topic for 1785, set by the vice-chancellor, Peter Peckard, was 'Anne liceat invitos in servitutem dare' (‘Is it lawful to enslave the unconsenting?’). Clarkson once more engaged in what he thought of as 'an innocent contest for literary honour' (Clarkson, History, vol. 1); but it changed his life.

Clarkson's essay

Clarkson took the title to be an invitation to consider the Atlantic slave trade, and read up the subject as well as he could in the few weeks available to him, beginning with Anthony Benezet's Historical Account of Guinea. What he discovered appalled him and oppressed him, both as a man and a Christian. He won the prize, but that now seemed a little thing, and after reading the essay in the Senate House in June he rode off to London, meditating the horrors of slavery all the way. While resting his horse at Wadesmill, Hertfordshire, he underwent a moment of conversion: 'a thought came into my mind, that if the contents of the Essay were true, it was time some person should see these calamities to their end' (Clarkson, History, vol. 1). In later years a small monument was erected to mark the spot. After twelve months of understandable hesitation, he accepted the call and gave up all idea of a church career, though he had already taken deacon's orders.

A Wisbech Quaker introduced Clarkson to the anti-slavery movement which, unknown to him, had been gathering strength for some years among Quakers in both Britain and America. They strengthened his sense of vocation and helped to publish a translation of his essay: it was brought out by the Quaker bookseller James Phillips (who became a close associate) in 1786 as An Essay of the Slavery and Commerce of the Human Species, Particularly the African. This was the first work in what was to be a lifetime of pamphleteering: in all he published twenty-three works, most of which dealt with slavery. The Essay had a great success and led to the creation of an informal committee to lobby MPs; its most important achievement was the recruiting of William Wilberforce, in which Clarkson played the chief part. Wilberforce was already sympathetic to anti-slavery; by the spring of 1787 he had committed himself to laying the question before the House of Commons, and on 22 May the committee for effecting the abolition of the slave trade was set up formally, with the object of giving Wilberforce every possible assistance. All the original twelve members were Quakers, except for Clarkson, Granville Sharp, and Philip Sansom. They voted the slave trade to be unjust and impolitic, and these two themes were to be constant in Clarkson's work until abolition was achieved.

Committee for the abolition of the slave trade

The committee was absolutely opposed to slavery itself, but decided that it could best proceed by attacking the slave trade alone, even to the extent of professing that its abolition would leave plantation slavery unaffected. Clarkson, the only committee member without professional commitments (he had a small private fortune), took on the essential job of seeking out every possible source of information, with an eye to an impending inquiry by the privy council and later proceedings in parliament. He had already made investigations in the port of London. Now he got on his horse again and set off for Bristol. He was to ride some 35,000 miles in the next seven years.

Initially Clarkson visited not only Bristol but Liverpool (the other main slaving port), Manchester, Bath, Gloucester, Worcester, Chester, Lancaster, and Birmingham. Wherever he went he received enthusiastic assistance from the Society of Friends; anti-slave-trade societies sprang up in his wake, and boroughs began to petition parliament for abolition—in the long run perhaps his most important achievement. His researches, pursued to the point of physical and mental exhaustion, and at substantial personal risk (an attempt was made to drown him at Liverpool) empowered the abolitionists for the first time with a comprehensive and irrefutable knowledge of the trade. Clarkson's findings filled his writings, such as his Essay on the Impolicy of the African Slave Trade (1788), which the committee assiduously printed and distributed in large numbers, and lay behind the twelve propositions which Wilberforce put to parliament in his first great abolitionist speech on 12 May 1789; Clarkson's influence was especially apparent in the point that the trade, far from being the nursery of British seamen, as its friends asserted, was in fact its graveyard, more seamen dying in that trade in one year than in the whole remaining trade of the country in two, and in the argument that slaves were not a necessary commodity for a flourishing trade with Africa.

John Clarkson joins the crusade

This last doctrine had important consequences for Thomas's brother John. In 1783 he had returned from six years of war in the West Indies. A half-pay lieutenant with scant prospects of promotion in the peacetime navy, he was drawn inevitably into the great crusade. He acted as his brother's secretary and then as one of his agents; he spent six months at Le Havre in 1788–9, studying the French slave trade, and was elected to the committee in 1791. It was to him that his colleagues turned on receiving the appeal of the black loyalists of Nova Scotia. These were former American slaves who had fought for the British in the war of independence, having been promised freedom and land in return; but they had received little of either. In 1790, hearing of Granville Sharp's ‘province of freedom’ in Sierra Leone, they asked the abolitionists for help in getting there. As a result the Sierra Leone Company was established, and John Clarkson was sent to Halifax to recruit settlers for the abolitionist colony. Aided by Thomas Peters, the black loyalist leader, he did so with immense success, and on 15 January 1792 led a fleet of fifteen vessels, carrying 1196 settlers, to Sierra Leone, which they reached on 6 March.

Although sixty-five of the Nova Scotians died during the voyage (John Clarkson nearly died himself) and Peters mutinied against Clarkson's leadership, the devotion of most of the migrants to Clarkson was unbounded: they called him their Moses. He was equally devoted to them, and laboured incessantly for their welfare, as superintendent and then as the colony's first governor, until his return on leave to England on 29 December 1792. For good or ill (Sierra Leone was the instrument by which official British imperialism gained a foothold in west Africa, and became a crown colony in 1808) it was the understanding between Clarkson and the Nova Scotians that got the colony through its very difficult first year. Clarkson's services were at first generally recognized. But great strains arose between him and the company directors, partly religious (he was not sympathetic to the insistent evangelicalism of Henry Thornton, the company chairman), partly because of the usual tension between head office and the man on the spot, and above all because Clarkson insisted on putting the views and interests of the Nova Scotians first, whereas the directors wanted the enterprise to show an early profit, so that they could compete successfully with the slave traders and bring to Africa Christianity and 'the Blessings of Industry and Civilization'. So Governor Clarkson never returned to Sierra Leone: the directors dismissed him on 23 April 1793, he having refused to resign. Thomas Clarkson resigned from the directorate soon afterwards, on the ostensible grounds that the company was getting too dependent on the British government.

The French Revolution

Thomas Clarkson's other affairs had not been going well. Year after year Wilberforce had introduced his motion for abolition in the House of Commons, and Clarkson had ridden up and down the land. Between them they had generated a national movement, but parliament never passed the bill, and the outbreak of the war with revolutionary France transformed the national temper. Clarkson's sympathy with the revolution soon became notorious (he had spent five months in Paris in 1789–90 trying to persuade the national assembly to abolish the slave trade) and brought hostility on the cause. His health was collapsing, and he had spent more than half his small capital in the cause of abolition. He decided to retire from the work; led by Wilberforce his friends raised £1500 in 1794 to compensate him for his disbursements.

John Clarkson's later life

On 24 April 1793, the day after his dismissal as governor of Sierra Leone, John Clarkson married Susan Lee (1769–1837), daughter of a successful banker. He became the manager of the Whitbreads' huge chalk and lime quarry at Purfleet in Essex, prospered, and in 1820 himself became a banker at Woodbridge, Suffolk. There were ten children of the marriage, but six predeceased their father, and only through one daughter, Sophia Maynard, did the Clarkson line survive into the twentieth century. His daughter Mary married Thomas Clarkson's son. John continued to take a keen if unobtrusive interest in Sierra Leone, and departed from the pursuits of his youth so far as to become in 1816 one of the principal founders of the Society for the Promotion of Permanent and Universal Peace. He never resumed an active part in the anti-slavery movement: nevertheless, he was having an abolitionist article read to him when he died of heart disease on 2 April 1828: his last words were, 'It is dreadful to think, after my brother and his friends have been labouring for forty years, that such things should still be.' He was buried in St Mary's churchyard, Woodbridge.

Thomas Clarkson's second campaign

Thomas Clarkson's retirement was transitory. He used it to re-establish his health, to buy for £1000 a small estate at Eusemere on Ullswater, to take up farming, and to marry Catherine Buck (1772–1856) of Bury St Edmunds in 1796. She shared Clarkson's radicalism (they had got to know each other through anti-slavery work) but her real value to her husband lay in her charm and intelligence, which captivated Crabb Robinson, her townsman, Samuel Taylor Coleridge, and William Wordsworth. She became one of Dorothy Wordsworth's closest friends, and Wordsworth admired Thomas so much that on the abolition of the slave trade in 1807 he addressed a sonnet to him ('Clarkson! it was an obstinate hill to climb'). Before then the Clarksons' only child, Thomas, was born, and they had returned to the south, as Catherine's health was thought to need a warmer climate. They lived at Bury St Edmunds from 1806 to 1816, and thereafter at Playford Hall, halfway between Ipswich and Woodbridge.

Clarkson's partnership with the Quakers strongly affected his religion. By 1795 he had renounced his Anglican orders, though he never submitted to the discipline of the Society of Friends. In 1815 he told Tsar Alexander I that he was 'nine parts in ten of their way of thinking' (Wilson, Thomas Clarkson, 145). In 1806 he published A Portraiture of Quakerism, which enjoyed great success, and in 1813 a biography of William Penn, which did not: it was the first scholarly treatment of its subject, but Clarkson had let the seventeenth century infect his style with its prolixity.

Clarkson returned with all his old vigour to the fight against the slave trade when, in 1804, the cause revived. He made another long journey on horseback, reviving old enthusiasm and obtaining new evidence, but his chief role, until the act abolishing the trade was passed in 1807, seems to have been in keeping sympathetic MPs up to the mark. At the climax, Wilberforce and the elder James Stephen were the most essential activists. In 1808 Clarkson published an invaluable two-volume History of the rise, progress, and accomplishment of the abolition of the African slave-trade by the British parliament. It contains much essential autobiographical and other information, but unfortunately its treatment of the 1804–7 period is incomplete and superficial.

The enforcement of the abolition act and Thomas Clarkson's last days

The years between 1808 and 1823 were largely taken up in attempts to ensure that the abolition act was enforced and, after the defeat of Napoleon, in forwarding the cause internationally. Clarkson became an occasional unofficial ambassador for anti-slavery: he was in Paris in 1814 and at the Congress of Aix-la-Chapelle in 1818. Universal abolition of the slave trade had become one of the main objects of British diplomacy, but it became clear to the agitators that they would have to reverse their policy: the trade would not die until slavery itself did. So in 1823 the Anti-Slavery Society was formed. Its purpose was to rouse public opinion to bring as much pressure as possible on parliament, and the new generation realized that for this they still needed Clarkson. He travelled again, though this time the network he activated was predominantly Anglican. He rode some 10,000 miles and achieved his masterpiece: by the summer of 1824, 777 petitions had been sent to parliament demanding gradual emancipation. When in 1830 the society adopted a policy of immediate emancipation Clarkson and Wilberforce appeared together for the last time to give their support.

Clarkson wrote incessantly in the cause until the act abolishing slavery in the British empire was passed in 1833. He lived for thirteen years more, troubled by failing eyesight and his son's premature death. Otherwise he was happy and never ceased to work for anti-slavery, lending his pen and his prestige particularly to the cause of abolition in the United States. He presided at the opening session of the grand anti-slavery convention in the Freemasons Hall on 12 June 1840; the moment when he blessed the proceedings was immortalized in a bad, if famous, painting by Benjamin Haydon. He died a pious, fairly easy death on 26 September 1846 at Playford, where he was buried on 2 October at St Mary's Church. Alone among the leading abolitionists he was not immediately commemorated in Westminster Abbey, apparently out of consideration for the susceptibilities of his Quaker friends; but a large monument to his memory, designed by Gilbert Scott, was erected in 1880 at Wisbech; and in 1996, to mark his sesquicentenary, a tablet was placed in Westminster Abbey close to the Wilberforce monument.

Final assessment

Clarkson was meanly attacked by R. I. and S. Wilberforce in their 1838 life of their father, William, but he effectively defended himself in his tract Strictures on a Life of William Wilberforce; Crabb Robinson had the last word when he wrote of the brothers, 'Such is their blindness that they see not even this—that to have been the forerunner, associate, and friend of Mr. Wilberforce is much more than to be the fruit of his loins' (Griggs, 177). More damaging to the fame of all the abolitionists was the view put forward in the mid-twentieth century by Eric Williams and his followers that slave emancipation owed little to the moralizing abolitionists, since slavery had become an obsolete economic system which British capitalists ended to suit themselves. This extreme view has been generally rejected. If it is now conceded that abolition would have been impossible but for the forces at work in the age of revolution, it is also understood that the abolitionists were themselves one of those forces, and without Wilberforce, Clarkson, and the rest slavery would not have been ended so soon and so completely, and perhaps not so peacefully. But nor should it be forgotten that British abolitionism was part of the great imperialist impulse of the age, as the story of Sierra Leone demonstrates.


  • E. G. Wilson, Thomas Clarkson: a biography (1989)
  • E. G. Wilson, John Clarkson and the African adventure (1980)
  • T. Clarkson, The history of the rise, progress, and accomplishment of the abolition of the African slave-trade by the British parliament, 2 vols. (1808)
  • T. Clarkson, Strictures on a life of William Wilberforce, by the Rev. W. Wilberforce and the Rev. S. Wilberforce (1838)
  • R. F. Scott, ed., Admissions to the College of St John the Evangelist in the University of Cambridge, 4: July 1767 – July 1802 (1931)
  • E. L. Griggs, Thomas Clarkson, the friend of slaves (1936)
  • J. W. St G. Walker, The black loyalists: the search for a promised land in Nova Scotia and Sierra Leone, 1783–1870 (1976)
  • C. Fyfe, A history of Sierra Leone (1962)
  • D. B. Davis, The problem of slavery in the age of revolution, 1770–1823 (1975)


  • BL, corresp. and papers, incl. family papers, Add. MSS 41262–41267
  • Boston PL, corresp. and papers
  • Doncaster Archives, Yorkshire, account of interview with tsar relating to slavery
  • Duke U., Perkins L., corresp.
  • Howard University Library, Washington, DC, corresp. and diary
  • Hunt. L., corresp. and papers
  • NL Wales, diary of a tour through Britain
  • St John Cam., corresp. and papers
  • University of Atlanta Library, corresp., journal, and papers
  • Wisbech and Fenland Museum, Wisbech, manuscripts
  • Bodl. Oxf., corresp. with William Wilberforce
  • Bodl. RH, letters to Anti-Slavery Society, corresp. with Thomas Buxton and others
  • DWL, letters to Henry Crabb Robinson
  • Hunt. L., letters to Zachary Macaulay
  • Lpool RO, letters to Lord Stanley
  • LUL, letters to Samuel Alexander
  • RS Friends, Lond., letters to William Allen, Cornelius Hanbury, and John Saunderson


  • C. F. von Breda, oils, 1788, NPG [see illus.]
  • W. Hazlitt, portrait, 1811, BM
  • A. E. Chalon, oils, 1824, Wilberforce House, Hull
  • T. S. Englehart, line engraving, pubd 1833 (after W. Hazlitt), BM
  • S. Lane, oils, exh. RA 1834, Wisbech Corporation, Cambridgeshire
  • J. Cochran, stipple, pubd 1836 (after S. Lane), BM, NPG
  • oils, 1838 (after S. Lane), St John Cam.
  • H. Room, oils, exh. RA 1839, St John Cam.
  • W. Behnes, marble bust, 1840, Guildhall, London
  • plaster bust, 1840, Ipswich Museum
  • C. Andrews, medallion; in possession of R. W. Cochran Patrick, 1894
  • A. E. Chalon, watercolour drawing, Wilberforce House, Hull
  • B. R. Haydon, group portrait, oils (The Anti-Slavery Society Convention, 1840), NPG
  • C. Turner, mezzotint (after A. E. Chalon), BM, NPG
  • mezzotint (after A. E. Chalon), NPG
  • plaster medallion (after medallion by C. Andrews), Scot. NPG