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# Battle of Thermopylae

## Overview
The Battle of Thermopylae (480 BCE) was a famous last stand by a Greek force led by King Leonidas I of Sparta against the massive Persian army of Xerxes I during the second Persian invasion of Greece. @t[=480 BCE]

## Key Facts
- Date: August 480 BCE (three days) @t[=480 BCE]
- Location: Thermopylae pass ("Hot Gates"), central Greece — a 15-metre-wide coastal gap with cliffs on one side and sea on the other
- Belligerents: Greek alliance vs. Persian Empire (Achaemenid)
- Commanders: Leonidas I (Sparta), Xerxes I (Persia)
- Result: Persian victory, but costly delay [^1]

## Context
The battle was part of the second Persian invasion of Greece. Xerxes I (r. 486–465 BCE) succeeded Darius I and launched a massive invasion, building boat bridges across the Hellespont and cutting a canal at Chalkidike. The oracle at Delphi had warned Athens to "fly to the world's end." [^3]

## The Battle
- Greek force of ~6,000–7,000 men held the narrow pass, including 300 Spartans, 700 Thespians, 1,000 Phokians, 1,000 Lokrians, 400 Thebans, 400 Corinthians, 2,120 Arcadians, and others [^3]
- The 300 Spartans were chosen specifically from men who had male heirs [^3]
- Greeks exploited the narrow terrain to negate Persian numerical advantage; Persian archers' light arrows were largely ineffective against bronze-armoured hoplites [^3]
- Xerxes first waited four days expecting the Greeks to flee; Leonidas' reply to a demand to lay down arms was *"Molōn labe"* ("Come and take them") [^3]
- On days one and two, even the elite Persian Immortals (10,000-strong) failed to break the Greek line [^3]
- Betrayed by Ephialtes of Trachis, who revealed the Anopaia mountain path to outflank the Greeks [^1][^3]
- Phokian troops guarding the Anopaia path withdrew to higher ground when the Immortals attacked, allowing the Persians to pass [^3]
- Leonidas dismissed most allies; ~300 Spartans, ~700 Thespians, and ~400 Thebans fought to the death in a rearguard action [^1]
- Leonidas was killed in the final stand; Xerxes ordered his head displayed on a stake [^3]
- Archaeological excavations at Kolonos Hill (the traditional last-stand site) have uncovered spearheads, arrowheads, armor fragments, and evidence of mass cremations consistent with ancient Greek funerary practices [^4]

## Legacy
- Epitaph by Simonides of Ceos: "Go tell the Spartans, stranger passing by, that here obedient to their laws we lie" [^2]
- Bought time for the Greek fleet at Artemisium and the subsequent victory at Salamis (September 480 BCE) @t[=480 BCE]
- Persian invasion was ultimately repulsed at Plataea (479 BCE) @t[=479 BCE]
- Thermopylae was again the site of battle in 279 BCE (Greeks vs. Gauls), 191 BCE (Romans defeated Antiochus III), and 1941 CE (Allied forces vs. Germany) [^3]
- Became the archetypal story of sacrifice against overwhelming odds

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[^1]: Herodotus, *Histories* 7.201–233
[^2]: Cartledge, P. *Thermopylae: The Battle That Changed the World* (2006)
[^3]: Cartwright, M. "Battle of Thermopylae." *World History Encyclopedia* (2013). https://www.worldhistory.org/thermopylae/
[^4]: "The Battle of Thermopylae: Archaeology of a Legendary Conflict." *The Archaeologist* (2025). https://thearchaeologist.squarespace.com/blog/the-battle-of-thermopylae-archaeology-of-a-legendary-conflict