These uninhabited islands are believed to be first discovered by Portuguese sailors Joao Goncalves Zarco and Tristao Vaz Teixeira in 1419, while sailing for Prince Henry the Navigator. A year later both captains sailed back to the islands and clamed them for Portugal. The islands were used mostly for agriculture growing sugar cane and grapes for sugar and wine. This was one of the first locations were West African Slaves were transported to work in the fields. The Madeira Islands are often referred to as the beginning of the Atlantic Slave trade as Portuguese traders along the African cost started to buy slaves from coastal kingdoms in Africa in exchange for guns and European goods. Slavery was abolished in 1761 by Portugal's Marquis of Pombal. During of the Napoleonic Wars, the British occupied the Islands for a period of time, making Madeira wine famous, but they eventually returned the islands to Portugal in 1814.  After a democratic revolution, the islands were given autonomy in 1976. Today they have their own government.