A city in southern Boeotia, in Greece. It was helped by Athens in 519 bc to defend itself against Thebes. Hence it alone of the Greek states helped the Athenians against the Persians at the Battle of Marathon (490), the Spartans arrived too late to take part in the battle. In 479 Plataea was the site of the crucial land battle of the Greek–Persian wars, when Mardonius was defeated. Its citizens were given refuge by Athens in 431 following a Theban attack, and a prolonged siege (429–427) led to the capture and the execution of the garrison who failed to escape.