8. Ephialtes of Trachis: The Persian Advance at Thermopylae
In 480 BCE, during the Battle of Thermopylae, Ephialtes, a local Greek, betrayed his homeland by revealing a secret mountain path to the Persian forces. This allowed the Persians to outflank the Greek defenders, leading to their defeat. Ephialtes’ name has since become synonymous with treachery. For more details, see the Ancient History Encyclopedia’s article on Ephialtes of Trachis. (worldhistory.org)
