The Spartans (documentary) the Spartan constitution into the militarised state we know of today. Homosexuality among men and boys was mandatory. The training of Spartan youths is explained, from their enrollment in the Agoge system right through to their attainment of citizenship. The class structure of the Lacedaemonian state (Helots, Perioeci, and the soldier-citizens themselves) is also covered. The episode ends with the battle of Thermopylae, in which 300 Spartans, including their king, Leonidas, were killed in action defending Greece from a Persian invasion. Part 2 opens with the retreat of the Persians, after Thermopylae and the battle of Salamis. Athens, which had
Leonidas I stood in higher regard, nor was Sparta less powerful in 478 BC than it had been in 481 BC. This selection of Leonidas to lead the defense of Greece against Xerxes' invasion led to Leonidas' death in the Battle of Thermopylae in 480 BC. Upon receiving a request from the confederated Greek forces to aid in defending Greece against the Persian invasion, Sparta consulted the Oracle at Delphi. The Oracle is said to have made the following prophecy in hexameter verse: In August 480 BC, Leonidas marched out of Sparta to meet Xerxes' army at Thermopylae with a small force