Slavery has a long tradition in Portugal. Muslims were taken prisoner and enslaved by Christians in the wars in Portugal during the 12th and 13th centuries. Although slavery in Muslim people declined in subsequent centuries a trade in African slaves was established in the 15th century following early expeditions to the continent. Portugal was the first European country to attempt to conquor and exploit Africa, establishing many forts along the coast and treaties with heads of state to help enable this trade in human beings. Initially the trade developed with Portugal as the hub of business, with goods and slaves traded through its capital Lisbon, with most slaves working in cities such as Lisbon, Évora and areas such as the Algarve. By the mid 16th century there were over 32,000 African slaves in Portugal, with the majority owned by the aristocracy, officials and religious institutions. However the number of slaves declined after demand for them in the Portuguese colony of Brazil led to an increase in prices, and gradually Brazil's economic importance, fundamentally linked to slavery, overtook that of Portugal.

Prince Henry the Navigator
Prince Henry the Navigator, the third son of the King of Portugal, was pivotal to early Portuguese exploration, navigation and science, inspiring an "Age of Discovery". He helped finance and organise many expeditions across the Atlantic, such as the one in 1415 to the North and West coasts of Africa, from which he learnt about trade in spices, gold and silver. The first slaves were brought to Portugal in 1441 for Prince Henry. Initially slaves were captured through outrageous means, including kidnapping and banditry. However Prince Henry ordered a change of practice, and so trading for slaves between Africans and Europeans became the norm.

Prince Henry the Navigator
© National Maritime Museum
Slavery in Portugal
Prince Henry established a slave market & fort in Arguin Bay in 1445 and they were brought back to Portugal. When a large slave auction was held in Lagos in that same year it was described by one witness as a "terrible scene of misery and disorder". By 1455 800 Africans were transported to Portugal annually.

Slave market in Lagos


By the 1470s Lisbon, Portugal's capital city, became the country's main slave port. The Portuguese slave trade started then not as a trans-Atlantic trade but as an old world trade, supplying slaves to Lisbon and hence onwards to Spain and Italy. In 1539 12,000 slaves were sold in the city's markets. This differed from other European countries' experience of the trade which developed much more in their colonies.

Lisbon also thrived off the businesses associated with slavery, with Portuguese goods exchanged for slaves, goods traded for slaves and goods produced by the slaves. People invested in the trade, and profited, and the Royal family took its share through taxation. African slaves were employed in a variety of occupations but increasingly they were to be found in urban employment such as domestic service.

Lisbon 1572-1618
Lisbon 1572-1618 © National Commission for the Commemoration of the Portuguese Discoveries
Slavery in Africa
tThe Portugeuse explored and claimed more of the West African coast and islands, with trade being established with Ghana, Benin, Gabon, and Mali in quick succession in the 1470s. The Portuguese establish treaties with some nations, often trading weapons for slaves. This had repurcussions, leading to warfare, starvation and ultimately depopulation in some regions.

In 1443 they were able to trade one horse for 25-30 slaves, by 1500 price of slaves rose to match the increased demand, one horse traded for 6 to 8 slaves.

Bases were established on small islands off the West Coast of Africa, the most important being Cape Verde and Sao Thome. These were used for collecting slaves traded from the mainland, who were then sent to Lisbon. The development of sugar cultivation on Sao Thome provided the blueprint for the larger plantation economy of the Americas. The free black and white populations mixed and rapidly and became creolised, which was common to Portuguese colonies.

The Kongo was devastated by its relationship with Portugal. First contact was in 1482 and initially the Kongolese were hopeful that it might be a beneficial relationship based on equality, and there was even an exchange of Ambassadors and the Royal family were baptised into the Catholic Church.

How the Portuguese appear before the King of Kongo
How the Portuguese appear before the King of Kongo Depiction of the meeting between the Portuguese expedition and the Kongolese Royal Family © National Maritime Museum

However over the next few decades the interest shifted towards the slave trade. The King at this time, Alfonso I, despite his efforts to ban the trade, lost half of his kingdom to slavery. In 1611 even the Portuguese King was so concerned at the impact slavery was having he tried to ban whites from the interior, but this was later rescinded.

By the late 15th century Portugal had extended its reach along the East coast of Africa trying to establish a dominance in trade. Their presence was strengthened when during the 1540s some East African Kingdoms ask for help from Portugal in fighting off Ottoman Turkish efforts to expand their empire. Portugal began slave trading in Ethiopia, Mozambique, Magagascar.

However during the 1570s African forces attacked Portuguese colonies in Mozambique and Ghana, a war errupted in Angola, and in 1585 there was a Swahili revolt on E African coast. By the 17th century African revolt and competition from other European powers reduced Portugal's trading to a few coastal outposts.

Pedro Alvares Cabral a Portuguese explorer was the first European to see Brazil in April 1500. He claimed it for Portugal, naming it the "Island of the True Cross" which later became Brazil named after a plant.

The Brazil he landed in was populated with between 2 and 6 million indigenous peoples, living as farmers or hunter-gatherers.

Major Portugeuse involvement in Brazil began in the second half of the 16th century with sugar as the main export. Plantation methods had already been established in their African island colonies. Success in Brazil increased the need for slaves, and so importation of slaves took off after 1550. This was exacerbated by the discovery of gold in the 1690s, the demand was sustained by the rise in coffee production during the C19th. Throughout this period Brazil imported approx 3.5 million slaves.

Brazilian sugar mill
© The Atlantic Slave Trade and Slave Life in the Americas: A Visual Record

As early as 1761 successive attempts were made to prohibit slavery and emancipate slaves within Portugal but they failed due to strong opposition. The buying of slaves from Africa was formally outlawed in 1830 but continued until the 1850s, whilst slavery itself continued until 1888.