A prisoner of war or enemy prisoner of war (EPW) is a person, whether civilian or combatant, who is held in custody by an enemy power during or immediately after an armed conflict. The earliest recorded usage of the phrase is dated 1660.
For most of human history, depending on the culture of the victors, combatants on the losing side in a battle could expect to be either slaughtered or enslaved

Slavery

Slavery is a system under which people are treated as property to be bought and sold, and are forced to work. Slaves can be held against their will from the time of their capture, purchase or birth, and deprived of the right to leave, to refuse to work, or to demand compensation...

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