Slavery in Ancient Greece was ubiquitous. As much as a third of the population of a polis such as Athens were slaves. In most of Hellas slavery was the result of being taken prisoner in war. A city taken in combat typically had its male citizens killed, the women and children were then sold into slavery. These slaves were sterilized so as to prevent generational bondage. Slaves were used in many ways from manual labor to teachers. A slave could earn money and might at times purchase their freedom. Slaves were looked upon with great disdain being called 'man footed things.'
The situation with Sparta was different. In order to perpetuate their unique system of military messes the Lacaedomanians enslaved the Greek population who lived in Messenia, the area of the Peloponnese adjacent. These helots were used to free the Spartans to pursue military training, making them the only professional soldiers in Hellas. The helots always greatly outnumbered the Spartans who used terror to keep the vast population of slaves cowed. At times the Euphors would suspend the usual murder laws and Spartan hoplites would go on killing sprees throughout the helot areas. Thucydides reports that the Spartans recruited a force of helots who were to be armed and used in battle. This was in fact a ruse to weed out those helots most likely revolt and all those who voluntered mysteriously disappeared.