The Battle of Thermopylae was the initial engagement between the Persian Empire and the confederation of Greek city-states led by Sparta during the Second Persian Invasion of Greece in 480 BC.

The vast Persian army first encounters significant Greek resistance at the narrow pass of Thermopylae (the Hot Gates), where he found an advance force of approximately 4,000 troops from various Greek city-states.

Unable to break through the Greek line, Persian King-of-Kings Xerxes was confounded until a local man named Ephialtes betrayed the Greek confederacy by informing him of a hidden trail over the mountains.

Xerxes sent a force around to the back of the Greek army holding the narrow pass of Thermopylae, outflanking and eventually overwhelming them.

Although this battle was not especially significant other than a delaying action against the Persian invasion, the story of the events is so compelling, combined with the sheer heroism displayed by the hugely-outnumbered Greek troops, that it has become the most famous last stand in history.

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