The warring Greek city-states of the classical period often found it advantageous to use slaves in their armed forces and to encourage rebellion or desertion among the slaves of their enemies. But since military service was highly esteemed, while the state of slavery was despised, classical Greek historians such as Herodotus, Thucydides and Xenophon tended not to discuss slave participation in war. This book examines the actual role of slaves in war, the neglect of it by historians, and the reasons for this reticence.