Abolitionism, or the abolitionist movement, is the movement to end slavery. In Western Europe and the Americas, abolitionism was a historic movement that sought to end the Atlantic slave trade and liberate the enslaved people, which eventually spread to eradicate slavery from the entire world. The British abolitionist movement started in the late 18th century when English and American Quakers began to question the morality of slavery. James Oglethorpe was among the first to articulate the Enlightenment case against slavery, banning it in the Province of Georgia on humanitarian grounds, and arguing against it in Parliament, and eventually encouraging his friends Granville Sharp and Hannah More to vigorously pursue the cause. Soon after Oglethorpe's death in 1785, Sharp and More united with William Wilberforce and others in forming the Clapham Sect. The Somersett case in 1772, in which a fugitive slave was freed with the judgement that slavery did not exist under English common law, helped launch the British movement to abolish slavery. Though anti-slavery sentiments were widespread by the late 18th century, many colonies and emerging nations continued to use slave labour: Dutch, French, British, Spanish, and Portuguese territories in the West Indies, South America, and the Southern United States. After the American Revolution established the United States, northern states, beginning with Pennsylvania in 1780, passed legislation during the next two decades abolishing slavery, sometimes by gradual emancipation. Massachusetts ratified a constitution that declared all men equal; freedom suits challenging slavery based on this principle brought an end to slavery in the state. Vermont, which existed as an unrecognized state from 1777 to 1791, abolished adult slavery in 1777. In other states, such as Virginia, similar declarations of rights were interpreted by the courts as not applicable to Africans and African Americans. During the following decades, the abolitionist movement grew in northern states, and Congress regulated the expansion of slavery in new states admitted to the union. In 1787, the Society for Effecting the Abolition of the Slave Trade was formed in London. Revolutionary France abolished slavery throughout its empire through the Law of 4 February 1794, but Napoleon restored it in 1802 as part of a programme to ensure sovereignty over its colonies. Haiti (then Saint-Domingue) formally declared independence from France in 1804 and became the first sovereign nation in the Western Hemisphere to unconditionally abolish slavery in the modern era. The northern states in the U.S. all