Battle of Thermopylae aware that his force was being outflanked, dismissed the bulk of the Greek army and remained to guard their retreat with 300 Spartans and 700 Thespians, fighting to the death. Others also reportedly remained, including up to 900 helots and 400 Thebans; these Thebans mostly reportedly surrendered. Themistocles was in command of the Greek Navy at Artemisium when he received news that the Persians had taken the pass at Thermopylae. Since the Greek strategy required both Thermopylae and Artemisium to be held, given their losses, it was decided to withdraw to Salamis. The Persians overran Boeotia and then captured the
Delian League to the Persian Empire, and Eretria was duly destroyed. However, the invasion ended in 490 BC with the decisive Athenian victory at the Battle of Marathon. Between the two invasions, Darius died, and responsibility for the war passed to his son Xerxes I. Xerxes then personally led a second Persian invasion of Greece in 480 BC, taking an enormous (although oft-exaggerated) army and navy to Greece. Those Greeks who chose to resist (the 'Allies') were defeated in the twin simultaneous battles of Thermopylae on land and Artemisium at sea. All of Greece except the Peloponnesus thus having fallen into Persian