The Slavery Abolition Act was an 1833 Act of the Parliament of the United Kingdom abolishing slavery throughout the British Empire. The Act was repealed in 1998 as part of a wider rationalisation of English statute law, but later anti-slavery legislation remains in force.
In 1772, Lord Mansfield's judgement in the Somersett's Case ( a man that was being forced to go to Jamaica when he doesn’t have to) freed a slave in England, which helped launch the movement to abolish slavery. While slavery was unsupported by law in England and Scotland and no authority could be exercised on slaves entering English or Scottish soil, this did not yet apply to the rest of the British Empire. In 1785, English poet William Cowper wrote: "We have no slaves at home – Then why abroad? Slaves cannot breathe in England; if their lungs receive our air, that moment they are free. They touch our country, and their shackles fall. That's noble, and bespeaks a nation proud. And jealous of the blessing. Spread it then, And let it circulate through every vein." By 1783, an anti-slavery movement to abolish the slave trade throughout the Empire had begun among the British public.
In 1808, after Parliament passed the Slave Trade Act of 1807, the Royal Navy established the West Africa Squadron. The squadron's task was to suppress the Atlantic slave trade by patrolling the coast of West Africa. It did suppress the slave trade, but did not stop it entirely. It is possible that, when slave ships were in danger of being captured by the Royal Navy, some captains may have ordered the slaves to be thrown into the sea to reduce the fines they had to pay. Between 1808 and 1860 the West Africa Squadron captured 1,600 slave ships and freed 150,000 Africans.
Notwithstanding what had been done to suppress the trade, further measures were soon discovered to be necessary, and in 1823, the Anti-Slavery Society was founded. Members included Joseph Sturge, Thomas Clarkson, William Wilberforce, Henry Brougham,...