1444 - First public sale of African slaves in Lagos, Portugal.

1482 - Portuguese start building first permanent slave trading post at Elmina, Gold Coast, now Ghana.

1510 - First slaves arrive in the Spanish colonies of South America, having travelled via Spain.

1518 - First direct shipment of slaves from Africa to the Americas.

1777 - State of Vermont, an independent Republic after the American Revolution, becomes first sovereign state to abolish slavery.

1780 - Transatlantic slave trade reaches peak.

1787 - The Society for the Abolition of the Slave Trade founded in Britain by Granville Sharp and Thomas Clarkson.

1792 - Denmark bans importation of slaves to its West Indies colonies the law only took effect from 1803.

1807 - Britain passes Abolition of the Slave Trade Act, outlawing British Atlantic slave trade.

- United States passes legislation banning the slave trade, effective from start of 1808.

1811 - Spain abolishes slavery, including in its colonies, though Cuba rejects ban and continues to deal in slaves.

1813 - Sweden bans slave trading

1814 - Netherlands bans slave trading.

1817 - France bans slave trading, but ban not effective until 1826.

1833 - Britain passes Abolition of Slavery Act, ordering gradual abolition of slavery in all British colonies. Plantation owners in the West Indies receive ?20 million in compensation.

- Great Britain and Spain sign a treaty prohibiting the slave trade

1819 - Portugal abolishes slave trade north of the equator.

- Britain places a naval squadron off the West African coast to enforce the ban on slave trading.

1823 - Britain's Anti-Slavery Society formed. Members include William Wilberforce.

1846 - Danish governor proclaims emancipation of slaves in Danish West Indies, abolishing slavery.

1848 - France abolishes slavery.

1851 - Brazil abolishes slave trading.

1858 - Portugal abolishes slavery in its colonies all slaves are subject to a 20-year apprenticeship.

1861 - Netherlands abolishes slavery in Dutch Caribbean colonies.

1862 - U.S. President Abraham Lincoln proclaims emancipation of slaves with effect from January 1, 1863; 13th Amendment of U.S. Constitution follows in 1865 banning slavery.

1886 - Slavery is abolished in Cuba.

1888 - Brazil abolishes slavery.

1926 - League of Nations adopts Slavery Convention abolishing slavery.

1948 - United Nations General Assembly adopts Universal Declaration of Human Rights, including article stating, "No one shall be held in slavery or servitude; slavery and the slave trade shall be prohibited in all their forms."

- Reuters