CLARKSON, THOMAS (1760-1846), English anti-slavery agitator, was born on the 28th of March 1760, at Wisbeach, in Cambridgeshire, where his father was headmaster of the free grammar school. He was educated at St Paul's school and at St John's College, Cambridge. Having taken the first place among the middle bachelors as Latin essayist, he succeeded in 1785 in gaining a similar honour among the senior bachelors. The subject appointed by the vice-chancellor, Dr Peckhard, was one in which he was himself deeply interested - Anne liceat invitos in servitutem dare? (Is it right to make men slaves against their will?). In preparing for this essay Clarkson consulted a number of works on African slavery, of which the chief was Benezet's Historical Survey of New Guinea; and the atrocities of which he read affected him so deeply that he determined to devote all his energies to effect the abolition of the slave trade, and gave up his intention of entering the church.
His first measure was to publish, with additions, an English translation of his prize essay (June 1786). He then commenced to search in all quarters for information concerning slavery. He soon discovered that the cause had already been taken up to some extent by others, most of whom belonged to the Society of Friends, and among the chief of whom were William Dillwyn, Joseph Wood and Granville Sharp. With the aid of these gentlemen, a committee of twelve was formed in May 1787 to do all that was possible to effect the abolition of the slave trade. Meanwhile Clarkson had also gained the sympathy of Wilberforce, Whitbread, Sturge and several other men of influence. Travelling from port to port, he now commenced to collect a large mass of evidence; and much of it was embodied in his Summary View of the Slave Trade, and the Probable Consequences of its Abolition, which, with a number of other anti-slavery tracts, was published by the committee. Pitt, Grenville, Fox and Burke looked favourably on the movement; in May 1788 Pitt introduced a parliamentary discussion on the subject, and Sir W. Dolben brought forward a bill providing that the number of slaves carried in a vessel should be proportional to its tonnage. A number of Liverpool and Bristol merchants obtained permission from the House to be heard by council against the bill, but on the 18th of June it passed the Commons. Soon after Clarkson published an Essay on the Impolicy of the Slave Trade; and for two months he was continuously engaged in travelling that he might meet men who were personally acquainted with the facts of the trade. From their lips he collected a considerable amount of evidence; but only nine could be prevailed upon to promise to appear before the privy council. Meanwhile other witnesses had been obtained by Wilberforce and the committee, and on the 12th of May 1789 the former led a debate on the subject in the House of Commons, in which he was seconded by Burke and supported by Pitt and Fox.
It was now the beginning of the French Revolution, and in the hope that he might arouse the French to sweep away slavery with other abuses, Clarkson crossed to Paris, where he remained six months. He found Necker head of the government, and obtained from him some sympathy but little help. Mirabeau, however, with his assistance, prepared a speech against slavery, to be delivered before the National Assembly, and the Marquis de la Fayette entered enthusiastically into his views. During this visit Clarkson met a deputation of negroes from Santo Domingo, who had come to France to present a petition to the National Assembly, desiring to be placed on an equal footing with the whites; but the storm of the Revolution permitted no substantial success to be achieved. Soon after his return home he engaged in a search, the apparent hopelessness of which finely displays his unshrinking laboriousness and his passionate enthusiasm. He desired to find some one who had himself witnessed the capture of the negroes in Africa; and a friend having met by chance a man-of-war's-man who had done so, Clarkson, though ignorant of the name and address of the sailor, set out in search of him, and actually discovered him. His last tour was undertaken in order to form anti-slavery committees in all the principal towns. At length, in the autumn of 1794, his health gave way, and he was obliged to cease active work. He now occupied his time in writing a History of the Abolition of the Slave Trade, which appeared in 1808. The bill for the abolition of the trade became law in 1807; but it was still necessary to secure the assent of the other powers to its principle. To obtain this was, under pressure of the public opinion created by Clarkson and his friends, one of the main objects of British diplomacy at the Congress of Vienna, and in February 1815 the trade was condemned by the powers. The question of concerting practical measures for its abolition was raised at the Congress of Aix-la-Chapelle in 1818, but without result. On this occasion Clarkson personally presented an address to the emperor Alexander I., who communicated it to the sovereigns of Austria and Prussia. In 1823 the Anti-Slavery Society was formed, and Clarkson was one of its vice-presidents. He was for some time blind from cataract; but several years before his death on the 26th of September 1846, his sight was restored.
Besides the works already mentioned, he published the Portraiture of Quakerism (1806), Memoirs of William Penn (1813), Researches, Antediluvian, Patriarchal and Historical (1836), intended as a history of the interference of Providence for man's spiritual good, and Strictures on several of the remarks concerning himself made in the Life of Wilberforce, in which his claim as originator of the anti-slavery movement is denied.
See the lives by Thomas Elmes (1876) and Thomas Taylor (1839).
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)