Abolitionism was a political movement that sought to abolish the practice of slavery and the worldwide slave trade. It began during the period of the Enlightenment and grew to large proportions in several nations during the nineteenth century, largely succeeding in its goals.

The trade in slaves in England was made illegal in 1102, and the last form of enforced servitude had disappeared in Britain by the beginning of the seventeenth century. But despite this the British economy developed upon slavery in the Americans and West Indian colonies of the British Empire.

By 1783, an anti-slavery movement was beginning among the British public. That year the first English abolitionist organisation was founded by a group of Quakers. The Quakers continued to be influential throughout the lifetime of the movement. On 17 June 1783 the issue was formally brought to government by Sir Cecil Wray (Member of Parliament for Retford), who presented the Quaker petition to Parliament.

In May 1787, the Committee for the Abolition of the Slave Trade was formed, referring to the Abolition of the Atlantic slave trade. There were many people, some African, some European by descent, who were fighting the slave trade. For example, in Britain Olaudah Equiano, whose autobiography went into nine editions in his lifetime. There was James Ramsay who had seen the cruelty of the trade at firsthand; Granville Sharp who fought legal cases including the Zong; Thomas Clarkson, and other members of the Clapham Sect of evangelical reformers, as well as Quakers.

In order to bring about the abolition of slavery it needed an Act of Parliament. The Anglican layman William Wilberforce in October 28, 1787 wrote in his diary ‘God Almighty has set before me two main objects, the suppression of the slave trade and the reformation of manners [morals]’ and with the support of Prime Minister Pitt he became the leader of the parliamentary campaign. Clarkson became the group's most prominent researcher about the slave trade, gaining firsthand accounts by interviewing sailors and former slaves at British ports such as Bristol, Liverpool and London.

Wilberforce and the Clapham Group tirelessly fought for 20years to see the ‘Abolition of the Slave Trade Act’ passed by the British Parliament on 25 March 1807 and the slavery Abolition Act on 23 August 1833. The Act imposed a fine of £100 for every slave found aboard a British ship. The intention was to entirely outlaw the slave trade within the British Empire, but the trade continued and captains in danger of being caught by the Royal Navy would often throw slaves into the sea to reduce the fine.

From 1839, the British and Foreign Anti-Slavery Society worked to outlaw slavery in other countries and to pressure the Government to help enforce the suppression of the slave trade by declaring slave traders pirates and pursuing them. This organization continues today as Anti-Slavery International.