Instruct: Given a question, retrieve relevant documents that can help answer the question.
Query: Did Portugal participate in the slave trade?
Slavery in Portugal occurred since before the country's formation. During the pre-independence period, inhabitants of the current Portuguese territory were often enslaved and enslaved others. After independence, during the existence of the Kingdom of Portugal, the country played a leading role in the Atlantic Slave Trade, which involved the mass trade and transportation of slaves from Africa and other parts of the world to the American continent. Slavery was abolished in Portugal in 1761 by the Marquês de Pombal. After the abolishment of slavery in Portugal, the Portuguese slave traders turned to clients in other countries where slavery was not yet abolished such as the United States of America.
Potential buyers made a careful examination of the "merchandise": they checked the state of health of a person who was often standing naked with wrists bound together. In Cairo, transactions involving eunuchs and concubines happened in private houses. Prices varied according to the slave's quality. Thomas Smee, the commander of the British research ship "Ternate", visited such a market in Zanzibar in 1811 and gave a detailed description:
Among many other European slave markets, Genoa, and Venice were some well-known markets, their importance and demand growing after the great plague of the 14th century which decimated much of the European work force.
The maritime town of Lagos, Portugal, was the first slave market created in Portugal for the sale of imported African slaves, the "Mercado de Escravos", which opened in 1444. In 1441, the first slaves were brought to Portugal from northern Mauritania. Prince Henry the Navigator, major sponsor of the Portuguese African expeditions, as of any other merchandise, taxed one fifth of the selling price of the slaves imported to Portugal. By the year 1552 African slaves made up 10 percent of the population of Lisbon. In the second half of the 16th century, the Crown gave up the monopoly on slave trade and the focus of European trade in African slaves shifted from import to Europe to slave transports directly to tropical colonies in the Americas—in the case of Portugal, especially Brazil. In the 15th century, one third of the slaves were resold to the African market in exchange of gold.
Among many other European slave markets, Genoa, and Venice were some well-known markets, their importance and demand growing after the great plague of the 14th century which decimated much of the European work force.
The maritime town of Lagos, Portugal, was the first slave market created in Portugal for the sale of imported African slaves, the "Mercado de Escravos", which opened in 1444. In 1441, the first slaves were brought to Portugal from northern Mauritania. Prince Henry the Navigator, major sponsor of the Portuguese African expeditions, as of any other merchandise, taxed one fifth of the selling price of the slaves imported to Portugal. By the year 1552 African slaves made up 10 percent of the population of Lisbon. In the second half of the 16th century, the Crown gave up the monopoly on slave trade and the focus of European trade in African slaves shifted from import to Europe to slave transports directly to tropical colonies in the Americas—in the case of Portugal, especially Brazil. In the 15th century, one third of the slaves were resold to the African market in exchange of gold. Slavery was abolished in mainland Portugal and Portuguese India in 1761. It was finally abolished in all Portuguese colonies in 1869.
A second cause of weakness in Portuguese Africa was the effects of three centuries of Atlantic slave trade which had roots in the older African slave trade. Once the Atlantic triangular trade got underway, many Portuguese (including many Brazilian traders) in Africa found little incentive to engage in any other kind of profitable economic activity. The economies of Guinea, Angola and Mozambique became almost entirely devoted to the export of slaves to the New World (plus gold and ivory where they were available) while on the islands, slaves were used to grow sugar for export. Colonial authorities did nothing to stop the slave trade, which had sympathisers even among the several native African tribes, and many became wealthy by supporting it, while the traders themselves generated huge profits with which they secured allies in Africa and Portugal.
After the Portuguese first made contact with Japan in 1543, a large scale slave trade developed in which Portuguese purchased Japanese as slaves in Japan and sold them to various locations overseas, including Portugal itself, throughout the sixteenth and seventeenth centuries. Many documents mention the large slave trade along with protests against the enslavement of Japanese. Japanese slaves are believed to be the first of their nation to end up in Europe, and the Portuguese purchased large numbers of Japanese slave girls to bring to Portugal for sexual purposes, as noted by the Church in 1555. King Sebastian feared that it was having a negative effect on Catholic proselytization since the slave trade in Japanese was growing to massive proportions, so he commanded that it be banned in 1571
After the Portuguese first made contact with Japan in 1543, a large scale slave trade developed in which Portuguese purchased Japanese as slaves in Japan and sold them to various locations overseas, including Portugal itself, throughout the sixteenth and seventeenth centuries. Many documents mention the large slave trade along with protests against the enslavement of Japanese. Japanese slaves are believed to be the first of their nation to end up in Europe, and the Portuguese purchased large numbers of Japanese slave girls to bring to Portugal for sexual purposes, as noted by the Church in 1555. King Sebastian feared that it was having a negative effect on Catholic proselytization since the slave trade in Japanese was growing to massive proportions, so he commanded that it be banned in 1571 Some Korean slaves were bought by the Portuguese and brought back to Portugal from Japan, where they had been among the tens of thousands of Korean prisoners of war transported to Japan during the Japanese invasions of Korea (1592–98). Historians pointed out that at the same time Hideyoshi expressed his indignation and outrage at the Portuguese trade in Japanese slaves, he himself was engaging in a mass slave trade of Korean prisoners of war in Japan. Chinese were bought in large numbers as slaves by the Portuguese in the 1520s. Japanese Christian Daimyos were mainly responsible for selling to the Portuguese their fellow Japanese. Japanese women and Japanese men, Javanese, Chinese, and Indians were all sold as slaves in Portugal.
In 1807, Parliament passed the Slave Trade Act of 1807, which outlawed the slave trade, but not slavery itself. This legislation imposed fines that did little to deter slave trade participants. Abolitionist Henry Brougham realized that trading had continued and as a new MP successfully introduced the Slave Trade Felony Act 1811 which at last made slavery a felony act through the empire. The Royal Navy established the West Africa Squadron 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. Between 1808 and 1860, the West Africa Squadron captured 1,600 slave ships and freed 150,000 Africans. They resettled many in Jamaica and the Bahamas. Britain also used its influence to coerce other countries to agree to treaties to end their slave trade and allow the Royal Navy to seize their slave ships.
After the Portuguese first made contact with Japan in 1543, a large scale slave trade developed in which Portuguese purchased Japanese as slaves in Japan and sold them to various locations overseas, including Portugal itself, throughout the sixteenth and seventeenth centuries. Many documents mention the large slave trade along with protests against the enslavement of Japanese. Japanese slaves are believed to be the first of their nation to end up in Europe, and the Portuguese purchased large numbers of Japanese slave girls to bring to Portugal for sexual purposes, as noted by the Church in 1555. Sebastian of Portugal feared that this was having a negative effect on Catholic proselytization since the slave trade in Japanese was growing to massive proportions, so he commanded that it be banned in 1571.
A large-scale slave trade developed in which Portuguese purchased Japanese as slaves in Japan and sold them to various locations overseas, including Portugal itself, throughout the sixteenth and seventeenth centuries. Many documents mention the large slave trade along with protests against the enslavement of Japanese. Japanese slaves are believed to be the first of their nation to end up in Europe, and the Portuguese purchased many Japanese slave girls to bring to Portugal for sexual purposes, as noted by the Church in 1555. King Sebastian feared that it was having a negative effect on Catholic proselytization since the slave trade in Japanese was growing to massive proportions, so he commanded that it be banned in 1571.
Throughout the 17th century, the increasing predations and surrounding of Portuguese trading posts in the East by the Dutch, English and French, and their rapidly growing intrusion into the Atlantic slave trade, undermined Portugal's near monopoly on the lucrative oceanic spice and slave trades. This sent the Portuguese spice trade into a long decline. The diversion of wealth from Portugal by the Habsburg monarchy to help support the Catholic side of the Thirty Years' War also strained the union, although Portugal did benefit from Spanish military power in retaining Brazil and in disrupting Dutch trade. Over time, Portugal became economically dependent on its colonies, first India and then Brazil.
After the Portuguese first made contact with Japan in 1543, a large scale slave trade developed in which Portuguese purchased Japanese as slaves in Japan and sold them to various locations overseas, including Portugal itself, throughout the sixteenth and seventeenth centuries. Many documents mention the large slave trade along with protests against the enslavement of Japanese. Japanese slaves are believed to be the first of their nation to end up in Europe, and the Portuguese purchased large numbers of Japanese slave girls to bring to Portugal for sexual purposes (see: Asian fetish), as noted by the Church in 1555. King Sebastian feared that it was having a negative effect on Catholic proselytization since the slave trade in Japanese was growing to massive proportions, so he commanded that it be banned in 1571.
After the Portuguese first made contact with Japan in 1543, a large scale slave trade developed in which Portuguese purchased Japanese as slaves in Japan and sold them to various locations overseas, including Portugal itself, throughout the sixteenth and seventeenth centuries.[14][15][16][17] Many documents mention the large slave trade along with protests against the enslavement of Japanese. Japanese slaves are believed to be the first of their nation to end up in Europe, and the Portuguese purchased large numbers of Japanese slave girls to bring to Portugal for sexual purposes, as noted by the Church in 1555. King Sebastian feared that it was having a negative effect on Catholic proselytization since the slave trade in Japanese was growing to massive proportions, so he commanded that it be banned in 1571.[18][19] Records of three Japanese slaves dating from the 16th century, named Gaspar Fernandes, Miguel and Ventura who ended up in Mexico showed that they were purchased by Portuguese slave traders in Japan, brought to Manila from where they were shipped to Mexico by their owner Perez.[20]
Al-Andalus Arab slave trade Atlantic slave trade Barbary pirates Economic history of Portugal Slavery in ancient Rome Slavery in Angola Slavery in Brazil Slavery in China Slavery in India
In an article written by anti-racism activist Tim Wise about such accusations of Jewish financial control, he wrote: 
Anti-Jewish propagandists have tried to exaggerate the role of Jews in the Atlantic slave trade. In the 1490s, the Jews were expelled from Spain and Portugal, at a time when trade with the New World was opening up, leading to their participation in Atlantic trading in general, and their participation in the Atlantic slave trade in particular. Jewish participation in the slave trade was significant in Brazil, Curaçao, Suriname, and Rhode Island, but it was otherwise modest or minimal, and Jews had virtually no role in the slave-trading of Britain or France. The Nation of Islam published "The Secret Relationship Between Blacks and Jews" in 1991, which asserted that Jews played a major role in the Atlantic slave trade. The book was widely criticized as anti-Semitic and led to additional scholarly research on the subject, including books such as "Jews and the American Slave Trade" by Saul S. Friedman, which concluded that Jewish involvement in the slave trade was "minimal" and comparable to other groups of slave-traders such as the English, and the accusations were an Antisemitic canard. In 1995 the American Historical Association (AHA) issued a statement condemning "any statement alleging that Jews played a disproportionate role in the Atlantic slave trade".
Shortly after the British Parliament outlawed British participation in the slave trade in 1807, the Royal Navy started to patrol the African coast and high seas, seizing British vessels suspected of engaging in the slave trade. After the Congress of Vienna and the ratification of various international agreements to restrict or outlaw the transatlantic trade, the West Africa Squadron, and to a lesser extent maritime patrols flying under the flags of Spain, Portugal, the Netherlands, Brazil, and the United States, also intercepted ships suspected of trafficking slaves in contravention of treaty provisions. In addition to the courts established in Freetown, tribunals to judge ships seized by anti-slaving patrols also operated in Havana, Rio de Janeiro, Luanda, Cape Verde, and St. Helena. 
Throughout the 17th century, the increasing predations and beleaguering of Portuguese trading posts in the East by the Dutch, English and French, and their rapidly growing intrusion into the Atlantic slave trade undermined Portugal's near monopoly on the lucrative oceanic spice and slave trades. This sent the Portuguese spice trade into a long decline. To a lesser extent, the diversion of wealth from Portugal by the Habsburg monarchy to help support the Catholic side of the Thirty Years' War also created strains within the union, although Portugal did benefit from Spanish military power in helping to retain Brazil and in disrupting Dutch trade. These events, and those that occurred at the end of the House of Aviz and the period of the Iberian Union, led Portugal to a state of dependency on its colonies, first India and then Brazil.
A large-scale slave trade developed in which Portuguese purchased Japanese as slaves in Japan and sold them to various locations overseas, including Portugal itself, throughout the sixteenth and seventeenth centuries. Many documents mention the large slave trade along with protests against the enslavement of Japanese. Japanese slaves are believed to be the first of their nation to end up in Europe, and the Portuguese purchased large numbers of Japanese slave girls to bring to Portugal for sexual purposes, as noted by the Church in 1555. King Sebastian feared that it was having a negative effect on Catholic proselytization since the slave trade in Japanese was growing to massive proporations, so he commanded that it be banned in 1571.
Slavery in Angola existed since the late 15th century when Portugal established contacts with the peoples living in what is the Northwest of the present country, and founded several trade posts on the coast. A number of those peoples, like the Imbangala and the Mbundu, were active slave traders for centuries (see African slave trade). In the late 16th century, Kingdom of Portugal's explorers founded the fortified settlement of Luanda, and later on minor trade posts and forts on the Kwanza River as well as on the Atlantic coast southwards until Benguela. The main component of their trading activities consisted in a heavy involvement in the Atlantic slave trade. Slave trafficking was abolished in 1836 by the Portuguese authorities.
The final major transformation of slave relationships came with the inconsistent emancipation efforts starting in the mid-19th century. As European authorities began to take over large parts of inland Africa starting in the 1870s, the colonial policies were often confusing on the issue. For example, even when slavery was deemed illegal, colonial authorities would return escaped slaves to their masters. Slavery persisted in some countries under colonial rule and in some instances it was not until independence that slavery practices were significantly transformed. Anti-colonial struggles in Africa often brought slaves and former slaves together with masters and former masters to fight for independence; however, this cooperation was short-lived and following independence political parties would often form based upon the stratifications of slaves and masters. In some parts of Africa, slavery and slavery-like practices continue to this day and the problem has proven to be difficult for governments and civil society to eliminate.
Efforts by Europeans against slavery and the slave trade began in the late 18th century and had a large impact on slavery in Africa. Portugal was the first country in the continent to abolish slavery in metropolitan Portugal and Portuguese India by a bill issued on 12 February 1761, but this did not affect their colonies of Brazil and Portuguese Africa. France abolished slavery in 1794. However, slavery was again allowed by Napoleon in 1802 and not abolished for good until 1848. In 1803, Denmark-Norway became the first country from Europe to implement a ban on the slave trade. Slavery itself was not banned until 1848. Britain followed in 1807 with the passage of the Abolition of the Slave Trade Act by Parliament. This law allowed stiff fines, increasing with the number of slaves transported, for captains of slave ships. Britain followed this with the Slavery Abolition Act 1833 which freed all slaves in the British Empire. British pressure on other countries resulted in them agreeing to end the slave trade from Africa. For example, the 1820 U.S. Law on Slave Trade made slave trading piracy, punishable by death. In addition, the Ottoman Empire abolished slave trade from Africa in 1847 under British pressure.
On 25 March 1807 Britain formally abolished the Slave Trade, prohibiting British subjects from trading in slaves, crewing slave ships, sponsoring slave ships, or fitting out slave ships. The Act also included a clause allowing the seizure of ships without slave cargoes on board but equipped to trade in slaves. In order to enforce this ruling in 1808 the Admiralty dispatched two vessels to police the African Coast. The small British force was empowered, due to the ongoing Napoleonic Wars, to stop any ship bearing the flag of an enemy nation, making suppression activities much easier. Portugal, however, was one of the largest slave trading nations and Britain's ally against France. So in February 1810 under diplomatic pressure, it signed a convention that allowed British ships to police Portuguese shipping, meaning Portugal could only trade in slaves from its own African possessions.
The First Atlantic system was the trade of enslaved Africans to, primarily, South American colonies of the Portuguese and Spanish empires; it accounted for slightly more than 3% of all Atlantic slave trade. It started (on a significant scale) in about 1502 and lasted until 1580 when Portugal was temporarily united with Spain. While the Portuguese were directly involved in trading enslaved peoples, the Spanish empire relied on the asiento system, awarding merchants (mostly from other countries) the license to trade enslaved people to their colonies. During the first Atlantic system, most of these traders were Portuguese, giving them a near-monopoly during the era. Some Dutch, English, and French traders also participated in the slave trade. After the union, Portugal came under Spanish legislation that prohibited it from directly engaging in the slave trade as a carrier. It became a target for the traditional enemies of Spain, losing a large share of the trade to the Dutch, English, and French.
Throughout the 17th century, the increasing predations and surrounding of Portuguese trading posts in the East by the Dutch, English and French, and their rapidly growing intrusion into the Atlantic slave trade, undermined Portugal's near monopoly on the lucrative oceanic spice and slave trades. This sent the Portuguese spice trade into a long decline. The diversion of wealth from Portugal by the Habsburg monarchy to support the Catholic side of the Thirty Years' War also created strains within the union, although Portugal did also benefit from Spanish military power in helping to retain Brazil and in disrupting Dutch trade. These events, and those that occurred at the end of Aviz dynasty and the period of Iberian Union, led Portugal to a state of dependency on its colonies, first India and then Brazil.
At the start of the 19th century, effective Portuguese governance in Africa south of the equator was limited. Portuguese Angola consisted of the areas around Luanda and Benguela, and a few almost independent towns over which Portugal claimed suzerainty, the most northerly of which was Ambriz. Portuguese Mozambique was limited to the Island of Mozambique and several other coastal trading posts or forts as far south as Delagoa Bay. In the late 18th and early 19th centuries, Angola's main function was to supply Brazil with slaves. This was facilitated, firstly by the development of coffee plantations in southern Brazil from the 1790s, and second, by the agreements of 1815 and 1817 between Britain and Portugal, which (on paper at least) limited Portuguese slave trading to areas south of the equator. This trade diminished after Brazilian independence in 1822, and more sharply following an agreement between Britain and Brazil in 1830 by which the Brazilian government prohibited further slave imports. To find slaves for export from the Angolan towns, Afro-Portuguese traders had penetrated as far inland as Katanga and Kazembe, but otherwise there was little penetration of the interior and no attempt to establish control there. When the Brazilian slave trade declined, slaves were used on Portuguese plantations which stretched inland of Luanda along the Cuanza River and to a lesser extent around Benguela. After Moçâmedes had been founded south of Benguela in 1840 and Ambriz had been occupied in 1855, Portugal controlled a continuous coastal strip from Ambriz to Moçâmedes, but little inland territory. Although Portugal claimed to control the Congo River estuary, Britain would at best accept it had limited rights in the Cabinda enclave north of the river, although these rights did not make Cabinda Portuguese territory.
After the Portuguese first made contact with Japan in 1543, a large scale slave trade developed in which Portuguese purchased Japanese as slaves in Japan and sold them to various locations overseas, including Portugal itself, throughout the sixteenth and seventeenth centuries. Many documents mention the large slave trade along with protests against the enslavement of Japanese. Japanese slaves are believed to be the first of their nation to end up in Europe, and the Portuguese purchased large numbers of Japanese slave girls to bring to Portugal for sexual purposes, as noted by the Church in 1555. Sebastian of Portugal feared that this was having a negative effect on Catholic proselytization since the slave trade in Japanese was growing to massive proportions, so he commanded that it be banned in 1571.
The Atlantic slave trade transferred African slaves from Africa to colonies in the New World. Much of the slave trade followed a triangular route: slaves were transported from Africa to the Caribbean, sugar from there to North America or Europe, and manufactured goods from there to Africa. Jews and descendants of Jews participated in the slave trade on both sides of the Atlantic, in the Netherlands, Spain, and Portugal on the eastern side, and in Brazil, Caribbean, and North America on the west side.