Ephialtes – The Most Notorious Traitor in Greek History

Ephialtes of Trachis, whose name means “nightmare” in Greek is regarded as one of the most notorious traitors in the history of Greece.

Ephialtes played a significant role in the Battle of Thermopylae in 480 BC by leading the Persian forces, under King Xerxes I, through a mountain pass called Anopaea, which bypassed the Greek defenses. This allowed the Persians to outflank the Greek forces led by King Leonidas of Sparta, ultimately leading to their defeat.

His name became synonymous with betrayal in Greek history. The name “Ephialtes” received a lasting stigma; it came to mean “nightmare” in the Greek language and to symbolize the archetypal traitor in Greek culture, similar to Judas in Christian culture and to Benedict Arnold in the American historical memory.

Historical accounts of Ephialtes at the Battle of Thermopylae

Herodotus, known as the “father of history”, provides an account of Ephialtes’ betrayal in Book 7 of his work “Histories.” He describes how Ephialtes, seeking a reward from the Persian King Xerxes I, revealed to him a secret mountain path that allowed the Persian army to bypass the Greek defense at the narrow pass of Thermopylae.

Ephialtes, motivated by a desire for personal gain, approached the Persian King Xerxes and informed him about a mountain path that would allow the Persian army to circumvent the Greek defense at Thermopylae, Herodotus wrote.

This path, known as the Anopaea Pass, led through the mountains and emerged behind the Greek position, thus enabling the Persians to outflank the Greek forces led by King Leonidas.

Xerxes, realizing the strategic significance of this information, dispatched a force under the command of Hydarnes to take advantage of the mountain path revealed by Ephialtes. This contingent of Persian troops successfully navigated the path and arrived behind the Greek lines, catching them by surprise.

As a result of Ephialtes’ betrayal and the Persian flanking maneuver, the Greek position at Thermopylae was compromised, ultimately leading to their defeat in the battle.

Herodotus portrays Ephialtes as a traitor motivated by personal gain, whose actions played a crucial role in the outcome of the Battle of Thermopylae.

Another ancient historian Diodorus Siculus provides a brief account of Ephialtes’ betrayal in his work “Bibliotheca historica” (Library of History). In Book 11, Chapter 4, he briefly mentions Ephialtes and his role in the Battle of Thermopylae. Plutarch also mentions Ephialtes and his role in his biography of the Athenian politician and general Themistocles.

What happened to the Greek traitor Ephialtes after Thermopylae?

From the historical accounts, we know that Ephialtes was a citizen of Trachis a city-state in central Greece located west of Thermopylae and was populated by the Malians. Its main town was also called Trachis until 426 BC when it was refounded as a Spartan colony and became Heraclea Trachinia.

But what happened to Ephialtes after the betrayal? Again Herodotus sheds some light:

“Ephialtes afterwards fled into Thessaly, for fear of the Lacedaemonians [ed: Spartans]; and he being so banished a price was put on his head by the Pylagori when the Amphictyons sat together in their council at Thermopylae [ed: Malis was a member of the Amphictyonic league];

“And a long time after that, having returned to Anticyra, he was slain by Athenades, a man of Trachis. It was for another cause (which I will tell in the latter part of my history) that this Athenades slew Ephialtes, but he was nonetheless honored for it by the Lacedaemonians.”

Battle of Thermopylae

It was most likely on August 7th of 480 BC that one of the most decisive battles ever recorded in Greek history, the Battle of Thermopylae, took place against the Persian Empire.

This battle, which has come to be the embodiment of the Greek ideal of freedom as later conceptualized by Aristotle, between two powerful forces in Central Greece would determine the fate of Western civilization.

The great Battle of Thermopylae and the valiant fight of the 300 fearless Spartans under the command of warrior King Leonidas against ten thousand elite Persian soldiers is one of the most brilliant moments in ancient Greek history.

In retrospect, it proved to be no less than a fight for the defense of Western Civilization itself. Although the battle itself was lost, the war was eventually won.