Ephialtes of Trachis

Ephialtes of Trachis showed the Persians the path around Thermopylae and gave his name to the Greek word for nightmare. He was a local man from Malis, the region around the pass, and Herodotus is the source for almost everything about him. The pass at Thermopylae was a strip of ground between the mountains and the sea, in places only a few metres wide, and the Greek force under Leonidas held it for two days against repeated Persian assaults in which numbers could not be brought to bear. There was, however, a mountain track — the Anopaea path — running over the ridge and rejoining the road behind the Greek position. Leonidas knew of it and had posted a thousand Phocians to guard it. Herodotus writes that Ephialtes came to Xerxes hoping for a great reward and told him about it, and guided the Immortals under Hydarnes along it during the night. They came on the Phocians at dawn, who heard the leaves under their feet, took the arrows to be aimed at them, and withdrew uphill; the Persians ignored them and continued down. Leonidas learned of it before dawn, dismissed most of the allied contingents, and stayed with the Spartans, the Thespians and the Thebans. Herodotus is careful to record that others were credited with the betrayal and that he names Ephialtes because the Greeks held him responsible. He fled and was later killed at Anticyra over an unrelated quarrel, and Sparta paid the reward to the killer anyway. The Greek word for nightmare is his name.

• Lived: 510 BCE – 470 BCE
• Nationality: Greek
• Roles: other