The ownership of one person by another, who controls the slave’s life and labour. Slaves are viewed by their owners as property, and are bought and sold accordingly. Slavery is closely associated with racial prejudice, the belief that one race is superior to another.

Slavery has a history going back to the earliest civilizations. In ancient Greece much of the economy relied on slaves and the sacred island of Delos served as the main slave market of the Aegean. It was very often the practice amongst the peoples of the ancient world to enslave prisoners-of-war, and that was the major source of slaves. The expansion of the Roman empire created an enormous number of slaves, and although the coming of Christianity helped to improve the slave’s lot, slavery proved persistent. Slavery was also commonplace in the Arab world (see slave trade, arab).

One of the most significant periods of slavery was the use of African slave labour in the plantations of the Caribbean and the southern states of the USA during the 18th and early 19th centuries (see slave trade, african; slave trade, abolition of).

During World War II the Germans made extensive use of slave labour. Able-bodied Jews, Russians, Slavs and others to whom the Germans believed themselves to be superior were forced to work as slaves. After the war, the word ‘slave’ was defined by the UN as anyone who cannot voluntarily withdraw his or her labour; the UN estimates that some 21 million such slaves exist, principally in Asia, Africa, and South America, where bonded labourers (persons who bind themselves over for a fixed period to pay off a debt or earn a fixed sum) and child slavery are widespread.