Slaves

Slavery and enslavement are both the state and the condition of being a slave, who is someone forbidden to quit their service for an enslaver, and who is treated by the enslaver as their property. Slavery typically involves the enslaved person being made to perform some form of work while also having their location dictated by the enslaver. Historically, when people were enslaved, it was often because they were indebted, or broke the law, or suffered a military defeat. The duration of their enslavement might be for life, or for a fixed period of time after which their freedom was granted. Individuals, then, usually became slaves involuntarily, due to force or coercion, although there was also voluntary slavery to pay a debt or obtain money for some purpose. In the course of human history, slavery was a typical feature of

civilization

, and legal in most societies, but it is now outlawed in all countries of the world, except as punishment for crime.

In ''chattel slavery'', the enslaved person is legally rendered the personal property (chattel) of the slave owner. In economics, the term ''de facto slavery'' describes the conditions of unfree labour and forced labour that most slaves endure.

In 2019, approximately 40 million people, of whom 26 percent were children, were enslaved throughout the world despite its being illegal. In the modern world, more than 50 percent of enslaved people provide forced labour, usually in the factories and sweatshops of the private sector of a country's economy. In industrialised countries, human trafficking is a modern variety of slavery; in non-industrialised countries, enslavement by debt bondage is a common form of enslaving a person, such as captive domestic servants, forced marriage, and child soldiers.

Terminology

The word slave arrived in English via the Old French . In Medieval Latin the word was and in Byzantine Greek .''Oxford English Dictionary'', 2nd edition 1989, ''s.v.'' ''slave'' Use of the word arose during the Early Medieval Period, when

Slavs

from Central and Eastern Europe (''Saqaliba'') were frequently enslaved by

Moors

from the

Iberian Peninsula

and North Africa.

There is a dispute among historians about whether terms such as "unfree labourer" or "enslaved person", rather than "slave", should be used when describing the victims of slavery. According to those proposing a change in terminology, ''slave'' perpetuates the crime of slavery in language by reducing its victims to a nonhuman noun instead of "carry

ng

them forward as people, not the property that they were". Other historians prefer ''slave'' because the term is familiar and shorter, or because it accurately reflects the inhumanity of slavery, with ''person'' implying a degree of autonomy that slavery does not allow.

Chattel slavery

As a social institution, chattel slavery denies the human agency of people, by legally dehumanising them into ''chattels'' (personal property) owned by the enslaver; therefore slaves give birth to slaves; the children of slaves are born enslaved, under legal doctrines, such as the 2100 BCE, Code of Ur-Nammu ("4. If a slave marries a slave, and that slave is set free, he does not leave the household. 5. If a slave marries a native .e. freeperson, he/she is to hand the firstborn son over to his owner. ...") or 1662 CE ''partus sequitur ventrem'' ("That which is brought forth follows the womb"). Like livestock, they can be bought and sold at will. Legally a chattel slave could be used sexually in any way her owner desired; females had no right to refuse, and in the Antebellum period in the United States many enslaved females were forced to become pregnant and give birth repeatedly, with no say about who impregnated them; their children were usually taken from them and sold, as if they were calves. (See children of the plantation for this practice in the United States.) While some form of slavery was common throughout human history, the specific notion of chattel slavery described above reached its modern extreme in the Americas. Beginning in the 18th century an abolitionist movement saw slavery as a violation of everyone's right as a person ("all men are created equal"), and sought to abolish it. This movement was successful; the last Western country to abolish slavery, Brazil, did so in 1888. The last third-world country to abolish slavery,

Mauritania

, did not do so until 1981.

Other examples of sexual slavery, often in military contexts, include detention in "rape camps" or "comfort stations," "

comfort women

", forced "marriages" to soldiers and other practices involving the treatment of women or men as chattel and, as such, violations of the peremptory norm prohibiting slavery.

Bonded labour

Indenture, otherwise known as bonded labour or debt bondage, is a form of unfree labour under which a person pledges himself or herself against a loan. The services required to repay the debt, and their duration, may be undefined. Debt bondage can be passed on from generation to generation, with children required to pay off their progenitors' debt. It is the most widespread form of slavery today. Debt bondage is most prevalent in South Asia. Money marriage refers to a marriage where a girl, usually, is married off to a man to settle debts owed by her parents. The Chukri System is a debt bondage system found in parts of

Bengal

where a female can be coerced into prostitution in order to pay off debts.

Dependents

The word "slavery" has also been used to refer to a legal state of dependency to somebody else. For example, in

Persia

, the situations and lives of such slaves could be better than those of common citizens.

Forced labour

Forced labour, or unfree labour, is sometimes used to describe an individual who is forced to work against their own will, under threat of violence or other punishment, but the generic term unfree labour is also used to describe chattel slavery, as well as any other situation in which a person is obliged to work against their own will, and a person's ability to work productively is under the complete control of another person. This may also include institutions not commonly classified as slavery, such as serfdom,

conscription

and penal labour. While some unfree labourers, such as serfs, have substantive, ''de jure'' legal or traditional rights, they also have no ability to terminate the arrangements under which they work and are frequently subject to forms of coercion, violence, and restrictions on their activities and movement outside their place of work.

Human trafficking primarily involves women and children forced into prostitution and is the fastest growing form of forced labour, with Thailand, Cambodia, India, Brazil and Mexico having been identified as leading hotspots of commercial sexual exploitation of children.

Child soldiers and child labor

In 2007, Human Rights Watch estimated that 200,000 to 300,000 children served as soldiers in current conflicts. More girls under 16 work as domestic workers than any other category of child labour, often sent to cities by parents living in rural poverty such as in restaveks in Haiti.

Forced marriage

Forced marriages or early marriages are often considered types of slavery. Forced marriage continues to be practiced in parts of the world including some parts of Asia and Africa and in immigrant communities in the West. Sacred prostitution is where girls and women are pledged to priests or those of higher castes, such as the practice of

Devadasi

in South Asia or fetish slaves in West Africa. Marriage by abduction occurs in many places in the world today, with a 2003 study finding a national average of 69% of marriages in Ethiopia being through abduction.

Other uses of the term

The word ''slavery'' is often used as a pejorative to describe any activity in which one is coerced into performing. Some argue that military drafts and other forms of coerced government labour constitute "state-operated slavery." Some libertarians and anarcho-capitalists view government taxation as a form of slavery.

"Slavery" has been used by some anti-psychiatry proponents to define involuntary psychiatric patients, claiming there are no unbiased physical tests for mental illness and yet the psychiatric patient must follow the orders of the psychiatrist. They assert that instead of chains to control the slave, the psychiatrist uses drugs to control the mind. Drapetomania was a psychiatric diagnosis for a slave who did not want to be a slave.

Some proponents of animal rights have applied the term ''slavery'' to the condition of some or all human-owned animals, arguing that their status is comparable to that of human slaves.

The labour market, as institutionalized under today's market economic systems, has been criticized by mainstream socialists and by anarcho-syndicalists, who utilise the term wage slavery as a pejorative or dysphemism for

wage labour

. Socialists draw parallels between the trade of labour as a commodity and slavery.

Cicero

is also known to have suggested such parallels.

Characteristics

Private versus state-owned slaves

Slaves have been owned privately by individuals but have also been under state ownership. For example, the kisaeng were women from low castes in pre modern Korea, who were owned by the state under government officials known as ''hojang'' and were required to provide entertainment to the aristocracy; in the 2020s some are denoted '' Kippumjo'' (the pleasure brigades of North Korea — serving as the concubines of the rulers of the state). "Tribute labor" is compulsory labor for the state and has been used in various iterations such as

corvée

, mit'a and repartimiento. The

internment camp

s of totalitarian regimes such as the Nazis and the Soviet Union placed increasing importance on the labor provided in those camps, leading to a growing tendency among historians to designate such systems as slavery.

Economics

Economists have modeled the circumstances under which slavery (and variants such as serfdom) appear and disappear. One observation is that slavery becomes more desirable for landowners where land is abundant but labour is scarce, such that rent is depressed and paid workers can demand high wages. If the opposite holds true, then it is more costly for landowners to guard the slaves than to employ paid workers who can demand only low wages because of the degree of competition. Thus, first slavery and then serfdom gradually decreased in Europe as the population grew. They were reintroduced in the Americas and in Russia as large areas of land with few inhabitants became available.

Slavery is more common when the tasks are relatively simple and thus easy to supervise, such as large-scale monocrops such as

sugarcane

and

cotton

, in which output depended on

economies of scale

. This enables systems of labour, such as the gang system in the United States, to become prominent on large plantations where field hands toiled with factory-like precision. Then, each work gang was based on an internal division of labour that assigned every member of the gang to a task and made each worker's performance dependent on the actions of the others. The enslaved chopped out the weeds that surrounded the cotton plants as well as excess sprouts. Plow gangs followed behind, stirring the soil near the plants and tossing it back around the plants. Thus, the gang system worked like an

assembly line

.

Since the 18th century, critics have argued that slavery retards technological advancement because the focus is on increasing the number of slaves doing simple tasks rather than upgrading their efficiency. For example, it is sometimes argued that, because of this narrow focus, technology in Greece – and later in Rome – was not applied to ease physical labour or improve manufacturing.

Scottish economist

Adam Smith

stated that free labour was economically better than slave labour, and that it was nearly impossible to end slavery in a free, democratic, or republican form of government since many of its legislators or political figures were slave owners, and would not punish themselves. He further stated that slaves would be better able to gain their freedom under centralized government, or a central authority like a king or church. Similar arguments appeared later in the works of

Auguste Comte

, especially given Smith's belief in the separation of powers, or what Comte called the "separation of the spiritual and the temporal" during the Middle Ages and the end of slavery, and Smith's criticism of masters, past and present. As Smith stated in the '' Lectures on Jurisprudence'', "The great power of the clergy thus concurring with that of the king set the slaves at liberty. But it was absolutely necessary both that the authority of the king and of the clergy should be great. Where ever any one of these was wanting, slavery still continues..."

Even after slavery became a criminal offense, slave owners could get high returns. According to researcher

Siddharth Kara

, the profits generated worldwide by all forms of slavery in 2007 were $91.2 billion. That was second only to drug trafficking, in terms of global criminal enterprises. At the time the weighted average global sales price of a slave was estimated to be approximately $340, with a high of $1,895 for the average trafficked sex slave, and a low of $40 to $50 for debt bondage slaves in part of Asia and Africa. The weighted average annual profits generated by a slave in 2007 was $3,175, with a low of an average $950 for bonded labour and $29,210 for a trafficked sex slave. Approximately 40% of slave profits each year were generated by trafficked sex slaves, representing slightly more than 4% of the world's 29 million slaves.

Identification

Throughout history, slaves were clothed in a distinctive fashion, particularly with respect to the frequent lack of footwear, as they were rather commonly forced to go

barefoot

. This was partly for economic reasons, but also served as a distinguishing feature, especially in South Africa and South America. For example, the

Cape Town

slave code stated that "Slaves must go barefoot and must carry passes." It also puts slaves at a physical disadvantage because of the lack of protection against environmental conditions and in confrontations, thereby making it more difficult to escape or to rebel against their owners.

This was the case in the majority of states. Most images from the respective historical period suggest that slaves were barefoot. Brother Riemer stated, "he slavesare, even in their most beautiful suit, obliged to go barefoot. Slaves were forbidden to wear shoes. This was a prime mark of distinction between the free and the bonded and no exceptions were permitted."

According to the Bible, shoes have been considered badges of freedom since antiquity: "But the father said to his servants, Bring forth the best robe, and put

t

on him; and put a ring on his hand, and shoes on

is

feet" (). This aspect can be viewed as an informal law in areas where slavery existed as any person sighted barefoot in public was assumed to be a slave.

In certain societies this rule continues. The Tuareg still unofficially practice slavery and force their slaves to remain barefoot.

Another widespread practice was branding, either to explicitly mark them as property or as punishment.

Legal rights

Depending upon the era and the country, slaves sometimes had a limited set of legal rights. For example, in the Province of New York, people who deliberately killed slaves were punishable under a 1686 statute. And, as already mentioned, certain legal rights attached to the nobi in Korea, to enslaved people in various African societies, and to black female slaves in the French colony of Louisiana. Giving slaves legal rights has sometimes been a matter of morality, but also sometimes a matter of self-interest. For example, in ancient Athens, protecting slaves from mistreatment simultaneously protected people who might be mistaken for slaves, and giving slaves limited property rights incentivized slaves to work harder to get more property. In the southern United States prior to the extirpation of slavery in 1865, a proslavery legal treatise reported that slaves accused of crimes typically had a legal right to counsel, freedom from double jeopardy, a right to trial by jury in graver cases, and the right to grand jury indictment, but they lacked many other rights such as white adults’ ability to control their own lives.

History

Some scholars differentiate ancient forms of slavery from the largely race-based slavery. The first type of slavery, sometimes called "just title servitude", was inflicted on prisoners of war, debtors, and other vulnerable people. Race-based slavery grew to immense proportions starting in the 14th century. It was argued even by some contemporary writers to be intrinsically immoral.

Early history

Slavery predates written records and has existed in many cultures. Slavery is rare among hunter-gatherer populations because it requires economic surpluses and a substantial population density. Thus, although it has existed among unusually resource-rich hunter gatherers, such as the American Indian peoples of the

salmon

-rich rivers of the Pacific Northwest coast, slavery became widespread only with the invention of agriculture during the Neolithic Revolution about 11,000 years ago.

In the earliest known records, slavery is treated as an established institution. The

Code of Hammurabi

(c. 1760 BC), for example, prescribed death for anyone who helped a slave escape or who sheltered a fugitive. The Bible mentions slavery as an established institution. Slavery was practiced in almost every ancient civilization. Such institutions included debt bondage, punishment for crime, the enslavement of prisoners of war, child abandonment, and the enslavement of slaves' offspring.

Classical antiquity

Africa

Slavery existed in

Pharaonic Egypt

, but studying it is complicated by terminology used by the Egyptians to refer to different classes of servitude over the course of history. Interpretation of the textual evidence of classes of slaves in

ancient Egypt

has been difficult to differentiate by word usage alone. The three apparent types of enslavement in Ancient Egypt: chattel slavery, bonded labour, and forced labour.

Asia

Slavery existed in ancient China as early as the

Shang dynasty

. Slavery was employed largely by governments as a means of maintaining a public labour force.

Europe

=Ancient Greece and Rome

=

Records of slavery in Ancient Greece date begin with Mycenaean Greece. Classical Athens had the largest slave population, with as many as 80,000 in the 6th and 5th centuries BC. As the Roman Republic expanded outward, entire populations were enslaved, across Europe and the Mediterranean. Slaves were used for labour, as well as for amusement (e.g.

gladiator

s and sex slaves). This oppression by an elite minority eventually led to slave revolts (see Roman Servile Wars); the Third Servile War was led by Spartacus.

By the late Republican era, slavery had become an economic pillar of Roman wealth, as well as Roman society. It is estimated that 25% or more of the population of Ancient Rome was enslaved, although the actual percentage is debated by scholars and varied from region to region. Slaves represented 15–25% of

Italy

's population, mostly war captives, especially from

Gaul

and Epirus. Estimates of the number of slaves in the

Roman Empire

suggest that the majority were scattered throughout the provinces outside of Italy. Generally, slaves in Italy were indigenous Italians. Foreigners (including both slaves and freedmen) born outside of Italy were estimated to have peaked at 5% of the total in the capital, where their number was largest. Those from outside of Europe were predominantly of Greek descent. Jewish slaves never fully assimilated into Roman society, remaining an identifiable minority. These slaves (especially the foreigners) had higher death rates and lower birth rates than natives and were sometimes subjected to mass expulsions. The average recorded age at death for the slaves in Rome was seventeen and a half years (17.2 for males; 17.9 for females).

Middle Ages

Africa

Slavery was widespread in

Africa

, which pursued both internal and external slave trade. In the Senegambia region, between 1300 and 1900, close to one-third of the population was enslaved. In early Islamic states of the western

Sahel

, including Ghana, Mali, Segou, and Songhai, about a third of the population were enslaved.

During the trans-Saharan slave trade, slaves from

West Africa

were transported across the

Sahara desert

to

North Africa

to be sold to Mediterranean and

Middle eastern

civilizations. The Indian Ocean slave trade, sometimes known as the east African slave trade, was multi-directional. Africans were sent as slaves to the Arabian Peninsula, to

Indian Ocean

islands (including

Madagascar

), to the Indian subcontinent, and later to the Americas. These traders captured Bantu peoples (Zanj) from the interior in present-day

Kenya

,

Mozambique

and

Tanzania

and brought them to the coast. There, the slaves gradually assimilated in rural areas, particularly on Unguja and Pemba islands.

Americas

Slavery in Mexico can be traced back to the

Aztecs

. Other Amerindians, such as the

Inca

of the Andes, the Tupinambá of Brazil, the Creek of Georgia, and the

Comanche

of Texas, also practiced slavery.

Slavery in Canada was practiced by First Nations and by European settlers. Slave-owning people of what became Canada were, for example, the fishing societies, such as the Yurok, that lived along the Pacific coast from Alaska to California, on what is sometimes described as the Pacific or Northern Northwest Coast. Some of the indigenous peoples of the Pacific Northwest Coast, such as the Haida and Tlingit and their descendants were slaves. Some nations in British Columbia continued to segregate and ostracize the descendants of slaves as late as the 1970s.

Asia

Slavery also existed in India, Japan and Vietnam.

= China

=

Many Han Chinese were enslaved in the process of the Mongol invasion of

China proper

. According to Japanese historians Sugiyama Masaaki (杉山正明) and Funada Yoshiyuki (舩田善之), Mongolian slaves were owned by Han Chinese during the Yuan dynasty.

=Korea

=
Slavery in Korea existed since before the Three Kingdoms of Korea period, . Slavery has been described as "very important in medieval Korea, probably more important than in any other East Asian country, but by the 16th century, population growth was making

t

unnecessary". Slavery went into decline around the 10th century but came back in the late Goryeo period when Korea also experienced multiple slave rebellions.

In the Joseon period of Korea, members of the slave class were known as ''nobi''. The nobi were socially indistinct from freemen (i.e., the middle and common classes) other than the ruling yangban class, and some possessed property rights, and legal and civil rights. Hence, some scholars argue that it is inappropriate to call them "slaves", while some scholars describe them as serfs. The nobi population could fluctuate up to about one-third of the total, but on average the nobi made up about 10% of the total population. In 1801, the majority of government nobi were emancipated, and by 1858, the nobi population stood at about 1.5 percent of the Korean population.

Europe

Large-scale trading in slaves was mainly confined to the South and East of early medieval Europe: the

Byzantine Empire

and the

Muslim world

were the destinations, while pagan

Central

and

Eastern Europe

(along with the Caucasus and Tartary) were important sources.

Viking

, Arab,

Greek

, and Radhanite

Jewish

merchants were all involved in the slave trade during the Early Middle Ages. The trade in European slaves reached a peak in the 10th century following the

Zanj Rebellion

which dampened the use of African slaves in the Arab world.

Slavery in early medieval Europe was so common that the

Catholic Church

repeatedly prohibited it, or at least the export of Christian slaves to non-Christian lands, as for example at the Council of Koblenz (922), the Council of London (1102) (which aimed mainly at the sale of English slaves to Ireland) and the Council of Armagh (1171). Serfdom, on the contrary, was widely accepted. In 1452,

Pope Nicholas V

issued the papal bull '' Dum Diversas'', granting the kings of Spain and Portugal the right to reduce any "Saracens (Muslims), pagans and any other unbelievers" to perpetual slavery, legitimizing the slave trade as a result of war. The approval of slavery under these conditions was reaffirmed and extended in his ''Romanus Pontifex'' bull of 1455.

=Britain

=
In Britain, slavery continued to be practiced following the fall of Rome, and sections of Hywel the Good's laws dealt with slaves in medieval Wales. The trade particularly picked up after the Viking invasions, with major markets at

Chester

and

Bristol

supplied by Danish, Mercian, and Welsh raiding of one another's borderlands. At the time of the ''Domesday Book'', nearly 10% of the English population were slaves.

William the Conqueror

introduced a law preventing the sale of slaves overseas. According to historian John Gillingham, by 1200 slavery in the British Isles was non-existent.

Slavery had never been authorized by statute within England and Wales, and in 1772, in the case Somerset v Stewart, Lord Mansfield declared that it was also unsupported within England by the common law. The slave trade was abolished by the Slave Trade Act 1807, although slavery remained legal in possessions outside Europe until the passage of the Slavery Abolition Act 1833 and the Indian Slavery Act, 1843.

However, when England began to have colonies in the Americas, and particularly from the 1640s, African slaves began to make their appearance in England and remained a presence until the eighteenth century. In Scotland, slaves continued to be sold as chattels until late in the eighteenth century (on the 2nd May, 1722, an advertisement appeared in the '' Edinburgh Evening Courant'', announcing that a stolen slave had been found, who would be sold to pay expenses, unless claimed within two weeks).

For nearly two hundred years in the history of coal mining in Scotland, miners were bonded to their "maisters" by a 1606 Act "Anent Coalyers and Salters". The Colliers and Salters (Scotland) Act 1775 stated that "many colliers and salters are in a state of slavery and bondage" and announced emancipation; those starting work after 1 July 1775 would not become slaves, while those already in a state of slavery could, after 7 or 10 years depending on their age, apply for a decree of the Sheriff's Court granting their freedom. Few could afford this, until a further law in 1799 established their freedom and made this slavery and bondage illegal.

=Ottoman Empire

=

The Byzantine-Ottoman wars and the Ottoman wars in Europe brought large numbers of slaves into the Islamic world. To staff its bureaucracy, the Ottoman Empire established a janissary system which seized hundreds of thousands of Christian boys through the devşirme system. They were well cared for but were legally slaves owned by the government and were not allowed to marry. They were never bought or sold. The empire gave them significant administrative and military roles. The system began about 1365; there were 135,000 janissaries in 1826, when the system ended.

After the Battle of Lepanto, 12,000 Christian galley slaves were recaptured and freed from the Ottoman fleet. Eastern Europe suffered a series of Tatar invasions, the goal of which was to loot and capture slaves for selling them to Ottomans as

jasyr

. Seventy-five Crimean Tatar raids were recorded into Poland–Lithuania between 1474 and 1569.

=Poland

=
Slavery in Poland was forbidden in the 15th century; in Lithuania, slavery was formally abolished in 1588; they were replaced by the second serfdom.

=Spain and Portugal

=
Medieval Spain and Portugal were the scene of almost constant Muslim invasion of the predominantly Christian area. Periodic raiding expeditions were sent from

Al-Andalus

to ravage the Iberian Christian kingdoms, bringing back booty and slaves. In a raid against Lisbon in 1189, for example, the

Almohad

caliph Yaqub al-Mansur took 3,000 female and child captives, while his governor of Córdoba, in a subsequent attack upon Silves, Portugal, in 1191, took 3,000 Christian slaves. From the 11th to the 19th century, North African Barbary Pirates engaged in '' Razzias'', raids on European coastal towns, to capture Christian slaves to sell at slave markets in places such as Algeria and Morocco.
The maritime town of

Lagos

was the first slave market created in Portugal (one of the earliest colonizers of the Americas) for the sale of imported African slaves – the ''

Mercado de Escravos

'', opened in 1444. In 1441, the first slaves were brought to Portugal from northern Mauritania.

By 1552, black African slaves made up 10% 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 – especially Brazil. In the 15th century one-third of the slaves were resold to the African market in exchange of gold.

=Russia

=

In Kievan Rus and Muscovy, slaves were usually classified as kholops. According to David P. Forsythe, "In 1649 up to three-quarters of Muscovy's peasants, or 13 to 14 million people, were serfs whose material lives were barely distinguishable from slaves. Perhaps another 1.5 million were formally enslaved, with Russian slaves serving Russian masters." Slavery remained a major institution in Russia until 1723, when

Peter the Great

converted the household slaves into house serfs. Russian agricultural slaves were formally converted into serfs earlier in 1679.

=Scandinavia

=
In Scandinavia, thralldom was abolished in the mid-14th century.

Early modern period

Africa

As recently as the early 1960s, Saudi Arabia's slave population was estimated at 300,000. Along with Yemen, the Saudis abolished slavery in 1962. Historically, slaves in the

Arab World

came from many different regions, including

Sub-Saharan Africa

(mainly ''Zanj''), the Caucasus (mainly

Circassians

), Central Asia (mainly Tartars), and

Central

and Eastern Europe (mainly Slavs [''Saqaliba'']).

Some historians assert that as many as 17 million people were sold into slavery on the coast of the Indian Ocean, the Middle East, and North Africa, and approximately 5 million African slaves were bought by Muslim slave traders and taken from Africa across the Red Sea, Indian Ocean, and Sahara desert between 1500 and 1900. The captives were sold throughout the Middle East. This trade accelerated as superior ships led to more trade and greater demand for labour on

plantation

s in the region. Eventually, tens of thousands of captives were being taken every year. The Indian Ocean slave trade was multi-directional and changed over time. To meet the demand for menial labour, Bantu slaves bought by east African slave traders from southeastern Africa were sold in cumulatively large numbers over the centuries to customers in Egypt, Arabia, the Persian Gulf, India, European colonies in the Far East, the Indian Ocean islands, Ethiopia and Somalia.

According to the ''Encyclopedia of African History'', "It is estimated that by the 1890s the largest slave population of the world, about 2 million people, was concentrated in the territories of the

Sokoto Caliphate

. The use of slave labour was extensive, especially in agriculture." The Anti-Slavery Society estimated there were 2 million slaves in Ethiopia in the early 1930s out of an estimated population of 8 to 16 million.

Slave labour in East Africa was drawn from the ''Zanj,'' Bantu peoples that lived along the East African coast. The Zanj were for centuries shipped as slaves by Arab traders to all the countries bordering the Indian Ocean. The Umayyad and Abbasid caliphs recruited many Zanj slaves as soldiers and, as early as 696, there were slave revolts of the Zanj against their Arab enslavers in Iraq. The

Zanj Rebellion

, a series of uprisings that took place between 869 and 883 near

Basra

(also known as Basara), situated in present-day Iraq, is believed to have involved enslaved Zanj that had originally been captured from the

African Great Lakes

region and areas further south in East Africa. It grew to involve over 500,000 slaves and free men who were imported from across the Muslim empire and claimed over "tens of thousands of lives in lower Iraq".
The Zanj who were taken as slaves to the Middle East were often used in strenuous agricultural work. As the plantation economy boomed and the Arabs became richer, agriculture and other manual labour work was thought to be demeaning. The resulting labour shortage led to an increased slave market.

In

Algiers

, the capital of Algeria, captured Christians and Europeans were forced into slavery. In about 1650, there were as many as 35,000 Christian slaves in Algiers. By one estimate, raids by Barbary pirates on coastal villages and ships extending from Italy to Iceland, enslaved an estimated 1 to 1.25 million Europeans between the 16th and 19th centuries. However, to this estimate is extrapolated by assuming the number of European, slaves captured by Barbary pirates, was constant for 250 years period:

Davis' numbers have been refuted by other historians, such as David Earle, who cautions that true picture of Europeans slaves is clouded by the fact the corsairs also seized non-Christian whites from eastern Europe. In addition, the number of slaves traded was hyperactive, with exaggerated estimates relying on peak years to calculate averages for entire centuries, or millennia. Hence, there were wide fluctuations year-to-year, particularly in the 18th and 19th centuries, given slave imports, and also given the fact that, prior to the 1840s, there are no consistent records. Middle East expert, John Wright, cautions that modern estimates are based on back-calculations from human observation. Such observations, across the late 16th and early 17th century observers, account for around 35,000 European Christian slaves held throughout this period on the Barbary Coast, across Tripoli, Tunis, but mostly in Algiers. The majority were sailors (particularly those who were English), taken with their ships, but others were fishermen and coastal villagers. However, most of these captives were people from lands close to Africa, particularly Spain and Italy. This eventually led to the bombardment of Algiers by an Anglo-Dutch fleet in 1816.

Under Omani Arabs, Zanzibar became East Africa's main slave port, with as many as 50,000 enslaved Africans passing through every year during the 19th century. Some historians estimate that between 11 and 18 million African slaves crossed the Red Sea, Indian Ocean, and Sahara Desert from 650 to 1900 AD. Eduard Rüppell described the losses of Sudanese slaves being transported on foot to Egypt: "after the Daftardar bey's 1822 campaign in the southern Nuba mountains, nearly 40,000 slaves were captured. However, through bad treatment, disease and desert travel barely 5,000 made it to Egypt.." W.A. Veenhoven wrote: "The German doctor, Gustav Nachtigal, an eye-witness, believed that for every slave who arrived at a market three or four died on the way ... Keltie (''The Partition of Africa'', London, 1920) believes that for every slave the Arabs brought to the coast at least six died on the way or during the slavers' raid.

Livingstone

puts the figure as high as ten to one."

Systems of servitude and slavery were common in parts of Africa, as they were in much of the

ancient world

. In many African societies where slavery was prevalent, the enslaved people were not treated as chattel slaves and were given certain rights in a system similar to indentured servitude elsewhere in the world. The forms of slavery in Africa were closely related to

kinship

structures. In many African communities, where land could not be owned, enslavement of individuals was used as a means to increase the influence a person had and expand connections. This made slaves a permanent part of a master's lineage and the children of slaves could become closely connected with the larger family ties. Children of slaves born into families could be integrated into the master's kinship group and rise to prominent positions within society, even to the level of chief in some instances. However, stigma often remained attached and there could be strict separations between slave members of a kinship group and those related to the master. Slavery was practiced in many different forms: debt slavery, enslavement of war captives, military slavery, and criminal slavery were all practiced in various parts of Africa. Slavery for domestic and court purposes was widespread throughout Africa.

When the Atlantic slave trade began, many of the local slave systems began supplying captives for chattel slave markets outside Africa. Although the Atlantic slave trade was not the only slave trade from Africa, it was the largest in volume and intensity. As Elikia M’bokolo wrote in ''

Le Monde diplomatique

'':

The trans-Atlantic slave trade peaked in the late 18th century, when the largest number of slaves were captured on raiding expeditions into the interior of West Africa. These expeditions were typically carried out by African kingdoms, such as the Oyo Empire (Yoruba), the Ashanti Empire, the kingdom of Dahomey, and the Aro Confederacy. It is estimated that about 15 percent of slaves died during the voyage, with mortality rates considerably higher in Africa itself in the process of capturing and transporting indigenous peoples to the ships.

Americas

Slavery in America remains a contentious issue and played a major role in the history and evolution of some countries, triggering a

revolution

, a civil war, and numerous rebellions.

In order to establish itself as an American empire, Spain had to fight against the relatively powerful civilizations of the New World. The Spanish people">Spanish