Abolitionism, or the abolitionist movement, is the political movement to end slavery and liberate enslaved individuals around the world.

The first country to fully outlaw slavery was France in 1315, but it was later used in its colonies. The first country to abolish and punish slavery for indigenous people was Spain with the New Laws in 1542. Under the actions of Toyotomi Hideyoshi, chattel slavery has been abolished across Japan since 1590, though other forms of forced labour were used during World War II. The first and only country to self-liberate from slavery was a former French colony, Haiti, as a result of the Revolution of 1791–1804. The British abolitionist movement began in the late 18th century, and the 1772 Somersett case established that slavery did not exist in English law. In 1807, the slave trade was made illegal throughout the British Empire, though existing slaves in British colonies were not liberated until the Slavery Abolition Act 1833. In the United States, Pennsylvania and Vermont were the first states to abolish slavery, Vermont in 1777 and Pennsylvania in 1780 (Vermont did not join the Union until 1791). By 1804, the rest of the northern states had abolished slavery, but it remained legal in southern states. By 1808, the United States outlawed the importation of slaves and in 1865 outlawed slavery except as a punishment.

In Eastern Europe, groups organized to abolish the enslavement of the Roma in Wallachia and Moldavia between 1843 and 1855, and to emancipate the serfs in Russia in 1861.