Causes and results of slavery

A main cause of the trade was the colonies that European countries were starting to develop. In America, for instance, which was a colony of England, there was a demand for many labourers for the sugar, tobacco and cotton plantations. Paid labourers were too expensive, and the indigenous people had largely been wiped out by disease and conflict, so the colonisers turned to Africa to provide cheap labour in the form of slaves.

The first shipment of slaves from West Africa to the Americas, across the Atlantic Ocean, was in the early 1500s. European, Arab and African merchants were now selling humans as well as gold, ivory and spices.

Slave Trade Routes 1650 - 1860 Image source

But responsibility for the slave trade is not simple. On the one hand, it was indeed the Europeans who purchased large numbers of Africans, and sent them far away to work in their colonies. On the other hand, Africans bear some responsibility themselves: some African societies had long had their own slaves, and they cooperated with the Europeans to sell other Africans into slavery. The Europeans relied on African merchants, soldiers and rulers to get slaves for them, which they then bought, at convenient seaports.

Africans were not strangers to the slave trade, or to the keeping of slaves. There had been considerable trading of Africans as slaves by Islamic Arab merchants in North Africa since the year 900. When Leo Africanus travelled to West Africa in the 1500s, he recorded in his The Description of Africa and of the Notable Things Therein Contained that, "slaves are the next highest commodity in the marketplace. There is a place where they sell countless slaves on market days." Criminals and prisoners of war, as well as political prisoners were often sold in the marketplaces in Gao, Jenne and Timbuktu.

Perhaps because slavery and slave trading had long existed in much of Africa (though perhaps in forms less brutal than the slavery practised in the Americas), Africans were untroubled by selling slaves to Europeans.

Case study: The kingdom of Kongo and the slave trade

At the same time as Great Zimbabwe was powerful, there was a large and powerful kingdom along the Congo River in Central Africa, known as the Kongo. Kongo was ruled by a manikongo, or king, and was divided into six provinces, each administered by a governor.

Artists depiction of the Kingdom of Kongo. Picture source: The Abolition Project,

The kingdom had an organised system of labour, taxation and trade, especially in iron and salt. It also had a currency, in the form of nzimbu shells from a nearby island. The Kongo Kingdom had been in place for around 200 years when the first Portuguese arrived on the coast.

In 1482, Diego Cão, a Portuguese explorer, visited the kingdom. The reigning manikongo, Nzinga Nkuwu, was impressed by the Portuguese and sent a delegation to visit Portugal. As a result, Portuguese missionaries, soldiers and artisans were welcomed to Mbanza, the capital of the kingdom. The missionaries targeted the Kongo leaders, and managed to convert Nzinga Nkuwu to Christianity. This led to divisions between the new Christians and followers of the traditional religions.

The next manikongo, Alfonso I, was raised as a Christian. He expanded trade links with the Portuguese, which included becoming involved in the slave trade. His people would raid neighbouring villages and states, selling the prisoners to the Europeans for a good price. This made the kingdom very wealthy for some years.

However, the slave trade eventually took its toll on the Kongo kingdom. Although the slave trade made some chiefs enormously wealthy, it ultimately undermined local economies and political stability as villages' vital labour forces were shipped overseas and slave raids and civil wars became commonplace. To meet the huge demand for slaves, the Kongolese began raiding further afield, and several groups fought back, including the Téké and the Kuba. This constant conflict distracted them from trade and weakened their defences. They soon became dependent on the Portuguese for assistance, especially in the Jaga Wars of 1568. The Kongo Kingdom never regained its former power. In the years that followed, the Kongo fought both for and against the Portuguese, eventually being colonised in 1885.

A breakaway group, the Ndongo, moved southwards. They called their kings angola. They were also later colonised by the Portuguese.

The Abolition project, Africa Before Transatlantic Slavery visit

Case study: The life of Gustavus Vassa

A good way of understanding the slave trade is to read the first-hand or eyewitness accounts written by actual slaves, after some were freed and taught to read and write in European languages. One of the most famous of these was written by Olaudah Equiano, who was captured as a young boy in southern Nigeria and sold into slavery in Europe. The Life of Gustavus Vassa (his slave name) was the first-ever slave autobiography. Here is an extract from his autobiography, a primary historical source:

Vassa's autobiography (above) was funded by abolitionists and helped to further the anti-slavery cause. Source:

The first object which saluted my eyes when I arrived on the coast, was the sea, and a slave ship, which was then riding at anchor, and waiting for its cargo. These filled me with astonishment, which was soon converted into terror, when I was carried on board. I was immediately handled, and tossed up to see if I were sound, by some of the crew; and I was now persuaded that I had gotten into a world of bad spirits, and that they were going to kill me. Their complexions, too, differing so much from ours, their long hair, and the language they spoke (which was very different from any I had ever heard) united to confirm me in this belief. Indeed, such were the horrors of my views and fears at the moment, that, if ten thousand worlds had been my own, I would have freely parted with them all to have exchanged my condition with that of the meanest slave in my own country. When I looked round the ship too, and saw a large furnace of copper boiling, and a multitude of black people of every description chained together, every one of their countenances expressing dejection and sorrow, I no longer doubted my fate; and, quite overpowered with horror and anguish, I fell motionless on the deck and fainted. When I recovered a little, I found some black people about me, who I believed were some of those who had brought me on board, and had been receiving their pay; they talked to me in order to cheer me, but all in vain. I asked them if we were not to be eaten by those white men with horrible looks, red faces, and long hair. They told me I was not: and one of the crew brought me a small portion of spirituous liquor in a wine glass, but, being afraid of him, I would not take it out of his hand. One of the blacks, therefore, took it from him and gave it to me, and I took a little down my palate, which, instead of reviving me, as they thought it would, threw me into the greatest consternation at the strange feeling it produced, having never tasted any such liquor before. Soon after this, the blacks who brought me on board went off, and left me abandoned to despair.

[later] We were conducted immediately to the merchant's yard, where we were all pent up together, like so many sheep in a fold, without regard to sex or age. As every object was new to me, every thing I saw filled me with surprise. What struck me first, was, that the houses were built with bricks and stones, and in every other respect different from those I had seen in Africa; but I was still more astonished on seeing people on horseback. I did not know what this could mean; and, indeed, I thought these people were full of nothing but magical arts. While I was in this astonishment, one of my fellow-prisoners spoke to a countryman of his, about the horses, who said they were the same kind they had in their country. I understood them, though they were from a distant part of Africa; and I thought it odd I had not seen any horses there; but afterwards, when I came to converse with different Africans, I found they had many horses amongst them, and much larger than those I then saw.

We were not many days in the merchant's custody, before we were sold after their usual manner, which is this: On a signal given, (as the beat of a drum) the buyers rush at once into the yard where the slaves are confined, and make choice of that parcel they like best. The noise and clamor with which this is attended, and the eagerness visible in the countenances of the buyers, serve not a little to increase the apprehension of terrified Africans, who may well be supposed to consider them as the ministers of that destruction to which they think themselves devoted. In this manner, without scruple, are relations and friends separated, most of them never to see each other again. I remember, in the vessel in which I was brought over, in the men's apartment, there were several brothers, who, in the sale, were sold in different lots; and it was very moving on this occasion, to see and hear their cries at parting. O, ye nominal Christians! Learned you this from your God, who says unto you, Do unto all men as you would men should do unto you? Is it not enough that we are torn from our country and friends, to toil for your luxury and lust of gain? Must every tender feeling be likewise sacrificed to your avarice? Are the dearest friends and relations, now rendered more dear by their separation from their kindred, still to be parted from each other, and thus prevented from cheering the gloom of slavery, with the small comfort of being together; and mingling their sufferings and sorrows? Why are parents to lose their children, brothers their sisters, husbands their wives? Surely, this is a new refinement in cruelty, which, while it has no advantage to atone for it, thus aggravates distress; and adds fresh horrors even to the wretchedness of slavery.

- Source: The Life of Gustavus Vassa by Olaudah Equiana, London, 1789

Abolition of the slave trade

If you get time try to watch the movie 'Amistad' in class. Picture source:

There was a great deal of resistance to slavery, even while it was still thriving. Many slaves themselves resisted capture by escaping or by jumping overboard from slave ships.

Examples of resistance include:

  • On the ship Amistad, a group of slaves rebelled and took control of the ship.
  • Queen Nzingha of Angola and King Maremba of the Kongo fought against the slave traders
  • Many Europeans found the idea of buying and selling human beings appalling.

The abolitionists and humanitarians in Europe and America were mostly Christian groups who saw the slave trade as a crime against God. They also believed that they could better spread the word of Christianity among free Africans.

Years of resistance and pressure, especially under the umbrella of the Anti-Slavery Society, eventually led the European governments to abolish slavery and emancipate or free the slaves, although it took a long time for this to happen in practice.

Some historians argue that the abolition of slavery was an economic, not a humanitarian, act. By the early 1800s the new captains of industry in England favoured abolition of slavery because they believed it was an inefficient and costly form of labour. Rather than buying slaves outright, and then having to provide at least a minimum of food and lodging, whether the slaves were productive or not, the English capitalists preferred to buy only the actual labour time of the so called free workers.

You can read more about the Industrial Revolution in Topic 3

Either way, Britain passed its Slavery Abolition Act in 1833, freeing all slaves in the British Empire, including South Africa. In North America, however, it was only after the American Civil War was fought in the 1860s that the slaves were freed.

Collections in the Archives