Battle of Thermopylae at Thermopylae, the Persians sent a mounted scout to reconnoitre. The Greeks allowed him to come up to the camp, observe them, and depart. Xerxes found the scout's reports of the size of the Greek force, and that the Spartans were indulging in callisthenics and combing their long hair, laughable. Seeking the counsel of Demaratus, an exiled Spartan king in his retinue, Xerxes was told the Spartans were preparing for battle, and it was their custom to adorn their hair when they were about to risk their lives. Demaratus called them "the bravest men in Greece" and warned the Great
Battle of Hysiae (417 BC) destroyed the town and fortress of Hysiae and had its male population executed. The campaign is described by the historians Thucydides (5.83.2), who actually fought in the war, and Diodorus Siculus (12.81.1), who wrote in the 1st century BC, over two hundred years later. Thucydides says that the Spartans marched against Argos in the winter of 418–417 BC with all their allies, but failed to take the city of Argos. The Spartans did, however, capture and destroy the Argive town of Hysiae, taking all the male citizens as hostages. The hostages were subsequently killed. With Hysiae destroyed, the Spartans left