Ancient Greece
At the Battle of Thermopylae, the Spartans were led by Leonidas and resisted the huge Persian army. After a couple of days, a traitor, Ephialtes, led the Persians around the pass behind the Greek army. Realising that defeat was inevitable, Leonidas released many of his men. Those who stayed knew that it would be a fight to the death. Leonides kept elite hoplites (foot soldiers) who had living sons at home. Some Thespians and Thebans who volunteered to stay.