Out of the 250,000 to 300,000 people in Athens, between a quarter and a third of them were slaves. Some slaves were captured in wars. Others were born slaves. Some people were forced into slavery when they could not afford to pay money they owed. Some slaves were owned by the state, like slave-archers from Scythia, who were used as "police" by the Athens government.

A few slaves had special skills, such as nurses, teachers, or pottery painters. Most slaves did the hardest and most unpleasant jobs. A lucky slave might save enough money to buy his freedom.