Slavery takes many forms, and although some of the more extreme and widespread of these forms have been virtually eradicated, more subtle forms still exist. The essence of slavery is ownership, its corollary is exploitation.
Slavery is also the looting of the wealth and resources of the victim countries and, when such exploitation went on for centuries, it is undeniable that the harm caused is huge and difficult, if not impossible, to quantify even if its reality is undoubted despite the time that has elapsed.
Self-sale or the sale of children to pay debts was recorded in Egypt in 2600 BC. Debt slavery and slavery from prisoners of war was widespread in all the near-Eastern cultures of that era. In the Greek and Roman civilizations slavery became a formal institution, but debt slavery ceased to be legal. After the fall of the Roman Empire slavery declined in western and central Europe, but persisted in southern Europe and the Middle East where it was given new impetus by Islam. With the colonization of the New World and the opening up of plantations, slave trade in negroes flourished and persisted until the advent of the anti-slavery movements in the 19th century. The liberation of these slaves did little to change attitudes in society towards them which still persist today.
The system flourished even among the most civilized peoples, among the Greeks and among the Romans, with whom the few imposed their will upon the many; and this power was exercised so unjustly and with such haughtiness that a crowd of slaves was regarded merely as so many chattels--not as persons, but as things. They were held to be outside the sphere of law, and without even the claim to retain and enjoy life. "Slaves are in the power of their masters, and this power is derived from the law of nations; for we find that among all nations masters have the power of life and death over their slaves, and whatever a slave earns belongs to his master." Owing to this state of moral confusion it became lawful for men to sell their slaves, to give them in exchange, to dispose of them by will, to beat them, to kill them, to abuse them by forcing them to serve for the gratification of evil passions and cruel superstitions; these things could be done, legally, with impunity, and in the light of heaven. Even those who were wisest in the pagan world, illustrious philosophers and learned jurisconsults, outraging the common feeling of humanity, succeeded in persuading themselves and others that slavery was simply a necessary condition of nature. Nor did they hesitate to assert that the slave class was very inferior to the freemen both in intelligence and perfection of bodily development, and therefore that slaves, as things wanting in reason and sense, ought in all things to be the instruments of the will, however rash and unworthy, of their masters. Such inhuman and wicked doctrines are to be specially detested; for, when once they are accepted, there is no form of oppression so wicked but that it will defend itself beneath some color of legality and justice. History is full of examples showing what a seedbed of crime, what a pest and calamity, this system has been for states. Hatreds are excited in the breasts of the slaves, and the masters are kept in a state of suspicion and perpetual dread; the slaves prepare to avenge themselves with the torches of the incendiary, and the masters continue the task of oppression with greater cruelty. States are disturbed alternately by the number of the slaves and by the violence of the masters, and so are easily overthrown; hence, in a word, come riots and seditions, pillage and fire. (Papal Writings, In Plurimis, 1888).
Slavery was therefore not a new phenomenon in the fourteenth century. It had been practised by other civilizations on other peoples. However, the massive and systematic way in which it was applied in Africa, on African peoples, was out of all proportion to what may have happened elsewhere. Carried out in the most inhuman ways, it was more costly in human lives, more destructive of the social fabric and the source of greater economic and cultural looting than humanity had every known. It was systematized and generalized to the point of being called the "black-slave trade".
Slavery-type practices remain very widespread throughout the world. From 1978 to 1981 among many instances reported to the ILO were those occurring in Tunisia, India, Italy, Taiwan, Columbia, Morocco, Palestine, Republic of Korea, USA (employment conditions of Mexican children), Spain and France. Slavery is illegal throughout the world except in the Sultanate of Muscat and Oman.
Overt ownership still exists and also the sale of slaves, but more widespread is the trade in women, the paying of bride-price or the inheritance of a brother's widow or widows. The 'adoption' of children for a price is practised in Latin America and Asia. Personal services and debt slavery exist in Asia, Africa and South America. Forced labour occurs in South Africa and other African countries, and in western Europe. Particularly in South Africa it forms part of a policy of racial segregation. In Europe it is the result of a traffic in immigrant workers and the restrictions placed on these by the governments and nationals of the countries in question.
The long and painful period during which the slave trade flourished was indeed begun by individuals but was subsequently shamelessly developed by companies and ultimately organized and directed by States, all of them European. For centuries, millions of men, women and children were torn from their society and taken forcibly to the Americas to be treated there in the most inhuman and degrading manner. Some of these people, after incredible sufferings, perished during the ocean crossings. African history in the period of slavery is marked by a series of crimes and all manner of violations of the rights of the human person which are beginning to be recognized but which have never formed the subject of any redress, while the Powers formerly responsible for this traffic continue to profit from it. Thus, for centuries the African continent witnessed the exploitation and pillage of its physical and human resources. Historically speaking, this exploitation is characteristic of the impunity for the serious violations of the rights of the peoples that suffered them.
It must immediately be said that the African peoples were not the only victims of slavery. The indigenous peoples of the New World were dispossessed of all their lands, which were exploited using the costless tabour that slavery supplied. The dual genocide committed, both upstream and downstream of slavery, has remained unpunished.
Slavery left Africa in a state of economic and cultural ruin marked by social ravages from which it has never recovered. The international community and the States which benefited from slavery have recognized the harm done to the victim peoples and apologies to Africa, even by the sovereign pontiff, are not sufficient to erase the odious crime and undo its consequences, including dire poverty, underdevelopment, destitution, disease and ignorance. These violations must be taken into account, although any prospect of decent redress requires a definite will and political courage.
The UK Home Office published a new report in 2018 that estimates that modern slavery costs the country up to £4.3 billion a year. This breaks down to each instance of the crime costing around £330,000 when support, lost earnings, and law enforcement costs are factored in. The findings prompted the Home Office to announce that it will review the effectiveness of the UK Modern Slavery Act passed in 2015.One member of the review panel said: “The exploitation and enslaving of men, women and children across the world and within the UK is one of the most shocking crimes and one of the most profitable. The Modern Slavery Act is a splendid piece of legislation but it is very important to review how well it is being implemented and how it could be improved.” The review will examine the nature of modern slavery offences, provisions for legal access and compensation to victims and improving the support given to child victims. The review will also look at what else can be done to strengthen the legislation and minimise the risk that goods and services available in the UK are produced through forced labour and slavery. In addition to reviewing anti-slavery legislation, the Home Office confirmed that it would spend £2m to expand the Independent Child Trafficking Advocates (ICTAs) scheme, which helps child victims of human trafficking.