A new study argues that the idea of Achilles having a single vulnerable spot on his heel emerged centuries after the Homeric epics and may have resulted from a combination of evolving mythology, ancient imagery and later confusion over anatomical terminology.
In the study “From Ankle to Heel: Revisiting the Anatomy of Achilles’ Mythical Invulnerability,” classical archaeologist and senior researcher at the University of Lausanne Barbara Kare examines how the familiar image of Achilles’ fatal heel developed.
Her central finding is striking: the Iliad never describes Achilles as invulnerable, nor does it identify his heel as a vulnerable spot.
Achilles was mortal in Homer
In Homer’s Iliad, Achilles is a mortal warrior who needs armour and divine protection because he can be wounded and killed.
The epic repeatedly foreshadows his death, although it ends before that event occurs.
That raises a fundamental question: how did the familiar story emerge in which Paris fires the fatal arrow and Apollo guides it into Achilles’ vulnerable heel?
And where did the story originate that Achilles’ mother, Thetis, dipped her infant son into the waters of the River Styx to make him invulnerable while holding him by the heel?
According to Kare’s study, neither element belongs to Homer’s original account.
Heel or ankle?
The earliest post-Homeric evidence points not to the heel but to the ankle area.
The lost Aethiopis, dating to the seventh century BC and known through Proclus’ summary, described Achilles’ death on the battlefield. Archaic traditions also appear to associate his fatal wound with the ankle rather than the heel.
Kare identifies evidence in archaic Greek imagery and in a fragmentary reference by the poet Stesichorus. Later writers, including Apollodorus and Quintus of Smyrna, used the term “sphuron”, referring to the ankle area, when describing Achilles’ fatal injury.
Archaic artistic representations reinforce the distinction.
A famous sixth-century BC Chalcidian amphora depicts Achilles after his death with an injury at the back of his lower leg rather than directly on his heel. A second arrow also appears embedded in his side.
Other representations similarly show two arrows rather than a single fatal wound, further challenging the later idea that Achilles possessed one uniquely vulnerable point.
An Etruscan engraved gemstone even depicts Achilles removing an arrow from his ankle.
Why the ankle mattered
The choice of the ankle may have carried a deeper symbolic meaning in the Homeric world.
Achilles is famously described as “podas okus” — swift-footed. Speed forms one of the defining characteristics of his heroic identity.
The ankle therefore represents more than just another part of his body. It forms the central joint connecting the lower leg and foot, allowing a person to stand, walk and run.
Homer also uses the word “astragalos”, or ankle, in broader anatomical contexts. In the Iliad, the term can refer to the joint between the neck and head, while in the Odyssey it appears in reference to the spine, in both cases in scenes involving fatal injuries.
In ancient Greek thought, joints carried particular significance because they represented points through which life could leave the body. An injury to the ankle of a hero whose defining characteristic was speed therefore carried a powerful symbolic meaning.
The talus and the myth of Talos
The connection between Achilles and the ankle becomes even more intriguing in Roman sources.
Kare points to Roman accounts that associate Achilles’ vulnerable point with the talus, the ankle bone.
The Roman writer Hyginus, for example, states in his Fabulae that an arrow struck Achilles in the talus, describing it as the only part of his body that the waters of the Styx had not touched.
Achilles was not the only mythological figure whose invulnerability centred on the ankle.
The story of Talos, the bronze automaton who guarded Crete, follows remarkably similar logic. Talos possessed an otherwise invulnerable body but had a single vein filled with ichor, the blood of the immortals, running from his neck to his ankles and sealed by a nail.
When the nail was removed, Talos died.
The parallels are striking: complete invulnerability, one point of weakness and that weakness located at the ankle.
How the ankle became the heel
The transition from ankle to heel appears to have happened gradually, with the history of the word talus playing a role.
The ancient meaning of talus did not correspond precisely to the modern anatomical definition. Medieval and early Renaissance anatomists sometimes translated the term incorrectly, associating it with the heel bone, or calcaneus, and at other times with the malleolus, the ankle bone.
The confusion gradually entered European languages.
The Latin talus became associated with words that now mean “heel” in several Romance languages, including talon in French, talón in Spanish and tallone in Italian.
A term originally associated with the ankle therefore helped contribute, through linguistic and anatomical confusion, to the modern association with the heel.
The birth of the “Achilles’ heel”
The metaphorical expression “Achilles’ heel”, meaning the single weakness of an otherwise powerful person, organisation or system, emerged much later.
The figurative use appears in English in the early 19th century, while the same image appears to have circulated in French as early as the late 18th century.
Over time, the heel became so firmly associated with Achilles’ vulnerability that the connection now seems inseparable from the ancient myth.
Yet the study offers a different picture: Homer’s Achilles had no famous heel. The vulnerable ankle came first, while the heel emerged later through centuries of mythmaking, artistic interpretation and linguistic confusion.
