The 300 Spartans Who Held the Pass at Thermopylae for Three Days in 480 BCE and Were Killed to a Man When Their Position Was Outflanked

The Persian invasion of mainland Greece in 480 BCE was the largest amphibious-and-overland military operation the eastern Mediterranean had ever seen. The Persian army under Xerxes I — having crossed the Hellespont in spring 480 BCE — numbered approximately 100,000 men (Herodotus’s much higher figures of two and three million are universally rejected by modern historians). The Persian fleet of approximately 1,200 warships supported the army’s progress along the coast.

The Greek defensive strategy was to delay the Persian advance at narrow choke-points while a Athenian-led naval engagement could be staged in restricted waters where the smaller Greek fleet could overcome the Persian numerical superiority. The agreed land choke-point was the pass of Thermopylae (“hot gates”) on the northwestern Greek coast — a narrow strip of land between Mount Kallidromos and the Malian Gulf, approximately 100 metres wide at the narrowest point.

The 300

The Greek defensive force was commanded by Leonidas I, one of the two hereditary kings of Sparta. The total Greek force at Thermopylae was approximately 7,000 — about 300 full Spartan citizen-soldiers (Spartiates), 700 Thespians, 400 Thebans, 1,000 Phocians, plus contingents from other allied Greek city-states. The 300 Spartans are the canonical number because they were Leonidas’s personal guard and because the rest of the Greek allies eventually withdrew.

The Spartan citizen-soldier was the elite heavy infantryman of the Greek world: extensively trained from age 7 in the Spartan agoge military education, equipped with bronze cuirass, shield, helmet, greaves, and a 2.5-metre thrusting spear. A unit of 300 Spartans was the largest force a single Spartan king conventionally commanded without parliamentary consultation; Leonidas had not been able to obtain Spartan parliamentary authorisation for a larger commitment because the festival of Carneia was in progress.

Three days

The Persian assault began on the morning of approximately 8 August 480 BCE (the dating is approximate; the exact day is not securely recovered). The first day’s attacks — by Median heavy infantry — broke against the Greek shield wall in the narrow pass. The Persian arrow volleys (which Herodotus reports could “blot out the sun”) were less effective than expected because the Greek heavy bronze armour was largely arrow-proof at standard engagement ranges.

The second day’s attacks — by the elite Persian Immortals — produced the same outcome. The Greek line held; Persian casualties were heavy.

On the evening of the second day a Greek defector — a local resident named Ephialtes from the nearby town of Malis — approached the Persian camp and offered to show the Persian army a mountain path around the pass. The path (the Anopaia path) ran south up over the Kallidromos massif and rejoined the coastal road behind the Greek position. The path was known to local shepherds but had not been considered defensible by the Greek command.

Xerxes sent his Persian Immortals corps along the Anopaia path on the evening of the second day. The path was guarded by approximately 1,000 Phocians from Leonidas’s force; the Phocians were taken by surprise at dawn on the third day, broke, and retreated up the mountain rather than down to warn Leonidas.

The third day

Leonidas was informed at dawn that the position would be outflanked within hours. He called a war council and dismissed most of the Greek allied force, who departed south through the (still uncut) road back to central Greece. The 300 Spartans, the 700 Thespians who volunteered to remain (the Thespian decision to fight to the end is sometimes underemphasised relative to the Spartan one), and the 400 Thebans (whose actual loyalty has been disputed — they may have been kept as hostages rather than willing combatants) stayed at the pass.

The reasons for Leonidas’s decision are not entirely clear from the contemporary sources. The conventional explanations are that he intended to delay the Persian flanking attack as long as possible to give the retreating Greek allies time to escape, that Spartan religious-military custom forbade a Spartiate from retreating before an enemy, that the Delphic oracle had earlier prophesied a Spartan king would die at Thermopylae and Leonidas was fulfilling the prophecy, or some combination of all three.

The third-day combat was hours of close-quarters infantry fighting. Leonidas was killed in the engagement; the Spartans fought over his body and retrieved it to a defensive position on a small hillock at the western end of the pass. The final hours of the battle were spear-and-shield combat at the hillock against Persian missile attack. The Persian troops eventually killed all the remaining Greeks with arrow volleys at close range.

What it produced

The three days at Thermopylae bought the rest of the Greek alliance approximately a week of preparation time. The naval engagement at Salamis on or about 29 September 480 BCE destroyed the Persian fleet. The land engagement at Plataea in August 479 BCE defeated the Persian army. The Persian invasion was over.

The subsequent Greek political memory of Thermopylae fixed it as the defining act of voluntary sacrifice for collective survival. The funerary inscription at the battlefield, attributed to the poet Simonides of Ceos, has been quoted continuously since:

Ὦ ξεῖν’, ἀγγέλλειν Λακεδαιμονίοις ὅτι τῇδε κείμεθα, τοῖς κείνων ῥήμασι πειθόμενοι.

Stranger, go tell the Spartans that here, obeying their laws, we lie.

Ephialtes the Greek defector reportedly fled to Thessaly after the battle and was killed there in 470 BCE — approximately a decade later — over a private quarrel that may or may not have been connected to his treason. The Spartan authorities had placed a price on his head; whether the killer collected the bounty is not recorded.

What is mythological

The “300” of the canonical story is a partial count. The Thespians and Thebans who died at Thermopylae alongside the Spartans bring the actual final-day Greek force to approximately 1,400. The Thespians have been under-credited in Anglo-American popular memory for two thousand years.

The “fight to the last man” narrative is essentially accurate — the available evidence supports the conclusion that the Spartans and Thespians did fight until the last of them was killed. The Theban contingent’s behaviour is less clear; some surrendered to the Persians in the final phase, which the surviving Greek tradition treated as evidence of their dubious loyalty.

The 1962 Hollywood film The 300 Spartans, the 1998 Frank Miller graphic novel 300, and the 2006 Zack Snyder film 300 are each more theatrical reconstructions than historical ones. The historical record is, however, surprisingly close to the mythological one — the unusual feature of Thermopylae is that the legend is, on the documentary record, mostly true.