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
Greece in the 5th century BC in Attica, attempting to take Athens, but were defeated at the Battle of Marathon by a Greek army of 9000 Athenian hoplites and 1000 Plateans led by the Athenian general Miltiades. The Persian fleet continued to Athens but, seeing it garrisoned, decided not to attempt an assault. During the subsequent period of peace, in 483 BC, a silver-bearing seam had been discovered in the Laurion (a small mountain range close to Athens), and the hundreds of talents mined there had paid for the construction of 200 warships to fight Aegina's piracy. In 480 BC, Darius' successor Xerxes I sent a