SLAVERY. - From the Old German *slav*, a term applied by the Germans to the Slavic peoples whom they took captive, slavery can be defined as the state of a person who belongs to another as a thing and is entirely subject to the will of another.
Captivity in war is the oldest and most universal way of falling into slavery, in that the prisoner becomes the property of whoever captured him. This is the *servitus* which Roman law admitted by virtue of the law of nations. Alongside captivity in war (though not in civil or brigand warfare) there is a slavery that arises either from natural condition—thus the child of a female slave is a slave—or from special circumstances in which the individual finds himself: thus in Rome one becomes a slave through insolvent debt, sold by the creditor *trans Tiberim* (i.e., outside Roman territory); one who evades military service or registration in the census lists (and who, by order of the consuls, is likewise sold *trans Tiberim*); a free woman who has relations with a slave against the will of his master; in the imperial period, one condemned *ad bestias* or *ad metallum* (servitude as a penalty).
I. Slavery in the Ancient World
The importance and extent of slavery in the ancient world is founded on the fact that the entire economy was based on manual labor, which, in countries with centralized regimes such as the Eastern Empires—where subjects were considered the property of the sovereign, his great feudal lords, and temple administrators of vast estates—was carried out by the inhabitants of the land. In contrast, in countries with free political systems (city-states), where citizens were absorbed by the cares of the state, labor was performed by enslaved workers.Aristotle himself, in the *Politics*, bases the necessity of slavery on the impossibility for the citizen to engage in work incompatible with his status as a free man, and justifies the right of war—which is its principal source—inasmuch as the victor demonstrates an external superiority that reveals his internal virtues. This viewpoint had already been expressed by Heraclitus, who asserts that war, by pitting forces against one another, sifts the strong from the weak and thereby founds and organizes society.
Plato, too, in the *Republic*, takes no account of the enslaved masses, since they neither have the time nor the means to acquire the spiritual culture that alone grants the right to govern the state.
In Athens during the 5th and 4th centuries BCE, the number of slaves is estimated at more than 100,000, either serving private households where they were born (οἰκογενεῖς) or the state (δημοσίου), which employed them in armed police service (τοξότοι) or other public duties. They could be manumitted, i.e., regain their freedom (ἀπελεύθεροι), in various ways: by being consecrated to a deity, proclaimed free by a herald, or by virtue of a will.
In Rome, in the earliest times, slaves were not numerous; names like *Marcipor* or *Gaipor*, meaning "slave of Marcus" or "slave of Gaius," indicate that a single slave sufficed. Later, their numbers grew greatly. Augustus fixed their number at twenty for urban households, but in the countryside (the *familia rustica* under the direction of a *vilicus*, who was himself a slave) the number was unlimited and certainly exceeded that of free men.

Schiaparelli, Luigi - Portrait, painting by Guglielmo Ghini (1933).