page_title: Second Persian invasion of Greece
section_title: August 480 BC: Thermopylae and Artemisium
hierarchical_section_title: Second Persian invasion of Greece / August 480 BC: Thermopylae and Artemisium
context_page_description: The second Persian invasion of Greece occurred during the Greco-Persian Wars, as King Xerxes I of Persia sought to conquer all of Greece. The invasion was a direct, if delayed, response to the defeat of the first Persian invasion of Greece at the Battle of Marathon, which ended Darius I's attempts to subjugate Greece. After Darius's death, his son Xerxes spent several years planning for the second invasion, mustering an enormous army and navy. The Athenians and Spartans led the Greek resistance. About a tenth of the Greek city-states joined the 'Allied' effort; most remained neutral or submitted to Xerxes.
  The invasion began in spring 480 BC, when the Persian army crossed the Hellespont and marched through Thrace and Macedon to Thessaly. The Persian advance was blocked at the pass of Thermopylae by a small Allied force under King Leonidas I of Sparta; simultaneously, the Persian fleet was blocked by an Allied fleet at the straits of Artemisium. At the famous Battle of Thermopylae, the Allied army held back the Persian army for three days, before they were outflanked by a mountain path and the Allied rearguard was trapped and annihilated.
context_section_description: When the Allies received the news that Xerxes was clearing paths around Mount Olympus, and thus intending to march towards Thermopylae, it was both the period of truce that accompanied the Olympic games, and the Spartan festival of Carneia, during both of which warfare was considered sacrilegious. Nevertheless, the Spartans considered the threat so grave that they despatched their king Leonidas I with his personal bodyguard (the Hippeis) of 300 men (in this case, the elite young soldiers in the Hippeis were replaced by veterans who already had sons). Leonidas was supported by contingents from the Peloponnesian cities allied to Sparta, and other forces that were picked up en route to Thermopylae. The Allies proceeded to occupy the pass, rebuilt the wall the Phocians had built at the narrowest point of the pass, and waited for Xerxes's arrival.
  When the Persians arrived at Thermopylae in mid-August, they initially waited for three days for the Allies to disperse. When Xerxes was eventually persuaded that the Allies intended to contest the pass, he sent his troops to attack. However, the Greek position was ideally suited to hoplite warfare, the Persian contingents being forced to attack the phalanx head on. The Allies thus withstood two full days of battle and everything Xerxes could throw at them. However, at the end of the second day, they were betrayed by a local resident named Ephialtes who revealed to Xerxes a mountain path that led behind the Allied lines. Xerxes then sent his elite guards, the Immortals on a night march to outflank the Allied. When he was made aware of this maneuver (while the Immortals were still en route), Leonidas dismissed the bulk of the Allied army, remaining to guard the rear with 300 Spartans, 700 Thespians, 400 Thebians and perhaps a few hundred others. On the third day of the battle, the remaining Allies sallied forth from the wall to meet the Persians and slaughter as many as they could. Ultimately, however, the Allied rearguard was annihilated, and the pass of Thermopylae opened to the Persians.
  Simultaneous with the battle at Thermopylae, an Allied naval force of 271 triremes defended the Straits of Artemisium against the Persians. Directly before Artemisium, the Persian fleet had been caught in a gale off the coast of Magnesia, losing many ships, but could still probably muster over 800 ships at the start of the battle. On the first day (also the first of the Battle of Thermopylae), the Persians detached 200 seaworthy ships, which were sent to sail around the eastern coast of Euboea. These ships were to round Euboea and block the line of retreat for the Allied fleet. Meanwhile, the Allies and the remaining Persians engaged in the late afternoon, the Allies having the better of the engagement and capturing 30 vessels. That evening, another storm occurred, wrecking the majority of the Persian detachment which had been sent around Euboea.
  On the second day of the battle, news reached the Allies that their lines of retreat were no longer threatened; they therefore resolved to maintain their position. They staged a hit-and-run attack on some Cilician ships, capturing and destroying them. On the third day, however, the Persian fleet attacked the Allies lines in full force. In a day of savage fighting, the Allies held on to their position, but suffered severe losses (half the Athenian fleet was damaged); nevertheless, the Allies inflicted equal losses on the Persian fleet. That evening, the Allies received news of the fate of Leonidas and the Allies at Thermopylae. Since the Allied fleet was badly damaged, and since it no longer needed to defend the flank of Thermopylae, they retreated from Artemisium to the island of Salamis.
caption: Battle of Thermopylae and movements to Salamis, 480 BC.