structural:expansion
The history of slavery spans many cultures, nationalities, and religions from ancient times to the present day. Likewise, its victims have come from many different ethnicities and religious groups. The social, economic, and legal positions of slaves have differed vastly in different systems of slavery in different times and places. Slavery has been found in some hunter-gatherer populations, particularly as hereditary slavery, but the conditions of agriculture with increasing social and economic complexity offer greater opportunity for mass chattel slavery. Slavery was institutionalized by the time the first civilizations emerged. Slavery features in the Mesopotamian Code of Hammurabi, which refers to it as an established institution.
Slavery was widespread in the ancient world in Europe, Asia, the Middle East, and Africa. It became less common throughout Europe during the Early Middle Ages, although it continued to be practised in some areas. Both Christians and Muslims captured and enslaved each other during centuries of warfare in the Mediterranean and Europe. Islamic slavery encompassed mainly Western and Central Asia, Northern and Eastern Africa, India, and Europe from the 7th to the 20th century. Islamic law approved of enslavement of non-Muslims, and slaves were trafficked from non-Muslim lands: from the North via the Balkan slave trade and the Crimean slave trade; from the East via the Bukhara slave trade; from the West via Andalusian slave trade; and from the South via the Trans-Saharan slave trade, the Red Sea slave trade and the Indian Ocean slave trade. Beginning in the 16th century, European merchants, starting mainly with merchants from Portugal, initiated the transatlantic slave trade. Few traders ventured far inland, attempting to avoid tropical diseases and violence. They mostly purchased imprisoned Africans from West African kingdoms, transporting them to Europe's colonies in the Americas. The merchants were sources of desired goods including guns, gunpowder, copper manillas, and cloth, and this demand for imported goods drove local wars and other means to the enslavement of Africans in ever greater numbers. In India and throughout the New World, people were forced into slavery to create the local workforce. The transatlantic slave trade was eventually curtailed after European and American governments passed legislation abolishing their nations' involvement in it. Practical efforts to enforce the abolition of slavery included the British Preventative Squadron and the American African Slave Trade Patrol, the abolition of slavery in the Americas, and the widespread imposition of European political control in Africa. In modern times human trafficking remains an international problem. An estimated 25–40 million people were enslaved as of 2013, the majority of these in Asia. During the 1983–2005 Second Sudanese Civil War, people were taken into slavery. Evidence emerged in the late 1990s of systematic child slavery and trafficking on cacao plantations in West Africa. Slavery in the 21st century continues and generates an estimated $150 billion in annual profits. Populations in regions with armed conflict are especially vulnerable, and modern transportation has made human trafficking easier. In 2019, there were an estimated 40 million people worldwide subject to some form of slavery – 25% were children. Sixty-one percent are used for forced labor, mostly in the private sector. Thirty-eight percent live in forced marriages. Other types of modern slavery are prison labor, sex trafficking, and sexual slavery.