<P> In 1787, he came into contact with Thomas Clarkson and a group of anti-slave - trade activists, including Granville Sharp, Hannah More and Charles Middleton . They persuaded Wilberforce to take on the cause of abolition, and he soon became one of the leading English abolitionists . He headed the parliamentary campaign against the British slave trade for twenty years until the passage of the Slave Trade Act of 1807 . </P> <P> Wilberforce was convinced of the importance of religion, morality and education . He championed causes and campaigns such as the Society for the Suppression of Vice, British missionary work in India, the creation of a free colony in Sierra Leone, the foundation of the Church Mission Society, and the Society for the Prevention of Cruelty to Animals . His underlying conservatism led him to support politically and socially controversial legislation, and resulted in criticism that he was ignoring injustices at home while campaigning for the enslaved abroad . </P> <P> In later years, Wilberforce supported the campaign for the complete abolition of slavery, and continued his involvement after 1826, when he resigned from Parliament because of his failing health . That campaign led to the Slavery Abolition Act 1833, which abolished slavery in most of the British Empire . Wilberforce died just three days after hearing that the passage of the Act through Parliament was assured . He was buried in Westminster Abbey, close to his friend William Pitt the Younger . </P> <P> Wilberforce was born in a house on the High Street of Hull, in the East Riding of Yorkshire, England, on 24 August 1759, the only son of Robert Wilberforce (1728--1768), a wealthy merchant, and his wife, Elizabeth Bird (1730--1798). His grandfather, William (1690--1774 or 1776), had made the family fortune in the maritime trade with Baltic countries, and had twice been elected mayor of Hull . </P>

Who was the first person fought against slavery system