Achilles (Ἀχιλλεύς‎), son of Peleus and Thetis; greatest of the Greek heroes in the Trojan War; central character of Homer's Iliad.

His name may be of Mycenaean Greek origin, meaning ‘a grief to the army’. If so, the destructive Wrath of Achilles, which forms the subject of the Iliad, must have been central to his mythical existence from the first.

In Homer he is king of Phthia, or ‘Hellas and Phthia’, in southern Thessaly (see phthiotis), and his people are the Myrmidons. As described at Il. 2. 681–5 the size of his kingdom, and of his contingent in the Trojan expedition (50 ships), is not outstanding. But in terms of martial prowess, which is the measure of excellence for a Homeric hero, Achilles' status as ‘best of the Achaeans’ is unquestioned. We are reminded of his absolute supremacy throughout the poem, even during those long stretches for which he is absent from the battlefield.

His character is complex. In many ways he carries the savage ethical code of the Homeric hero to its ultimate and terrifying conclusion. When Agamemnon steals his concubine Briseis in Il. 1, his anger at the insult to his personal honour is natural and approved by gods and men; but he carries this anger beyond any normal limit when he refuses an offer of immense compensation in Il. 9. Again, when he finally re-enters the war (Il.19) after the death of his friend Patroclus, his ruthless massacre of Trojans, culminating in the killing of Hector (Il.22), expresses a ‘heroic’ desire for revenge; but this too is taken beyond normal bounds by his contemptuous maltreatment of Hector's dead body (Il. 22. 395–404, 24. 14–22).

But what makes Achilles remarkable is the way in which his extreme expression of the ‘heroic code’ is combined with a unique degree of insight and self-knowledge. Unlike Hector, for instance, Achilles knows well that he is soon to die. In his great speech at Il. 9. 308–429 he calls the entire code into question, saying that he would rather live quietly at home than pursue glory in the Trojan War; but it is his ‘heroic’ rage against Agamemnon that has brought him to this point. In his encounter with Lycaon at Il. 21. 34–135, his sense of common mortality (the fact that Patroclus has died and Achilles himself will die) is a reason, not for sparing his suppliant, but for killing him in cold blood. Finally at Il. 24, when Priam begs him to release Hector's body, it is human feeling, as well as the gods' command, that makes him yield (507–70); but even then he accepts a ransom, and his anger still threatens to break out afresh (568–70, 584–6).

Later writers seldom treated the subject-matter of the Iliad (though Aeschylus did so, devoting a probable trilogy to the events of Il. 16–24 and portraying Achilles and Patroclus as lovers: fr. 134a). But they did provide many further details of Achilles' career, often derived from cyclic epics (see epic cycle) such as the Cypria and Aethiopis. As a boy he was brought up by the wise centaur Chiron on Mt. Pelion. Later his mother Thetis, knowing that he would be killed if he joined the expedition to Troy, hid him at the court of King Lycomedes on Scyros, disguised as a girl (this episode is treated in the unfinished Achilleis of Statius). There he fell in love with the king's daughter Deidamia, who bore him a son, Neoptolemus (1). Odysseus discovered his identity by trickery (the subject of Euripides' lost Scyrians) and he joined the Greek army at Aulis, where he was involved in the story of Iphigenia (see Euripides' Iphigenia at Aulis). On the way to Troy he wounded Telephus (1). His exploits at Troy included the ambush and killing of Priam's son Troilus. After the events of the Iliad he killed two allies of the Trojans: the Amazon queen Penthesilea and the Ethiopian king Memnon (1). Finally he was himself killed by Paris and Apollo (as predicted at Il. 22. 358–60). Then, by a tradition dating back to the Aethiopis, Thetis translated him to a blessed existence on the White Island (mod. Insula Şerpilor, Ostriv Zmiyinyy) in the Euxine Sea, where some say that he is accompanied by Helen (but Ibycus, fr. 10 Page, curiously has him married in Elysium to Medea). All this contradicts Od. 11. 467–540, 24. 15–98, where his shade is in the Underworld.

The fight over his body, and his funeral, are described at Od. 24. 36–94. His famous arms (described at Il. 18. 478–613) were then given to Odysseus (see Sophocles' Ajax). After the fall of Troy his ghost demanded the sacrifice of Polyxena (see Euripides' Hecuba).

The ‘Achilles heel’ is a late addition to the story, at least to judge from our literary sources: allusions at Hyg. Fab. 107 and Stat. Achil. 1. 134, 269, 480 but no full account until Servius and ‘Lactantus Placidus’ (though vase paintings showing an arrow directed at Achilles’ foot suggest that some version was known much earlier). By this account Thetis sought to make the infant Achilles invulnerable by dipping him in the Styx, but omitted to dip the ankle (rather than the heel) by which she held him, and it was there that he received his death-wound. An alternative story, from the Aegimius (Hes. Fr. 300 M-W), was that Thetis had earlier children by Peleus and placed them in boiling water to test whether they were immortal, but, as the results proved negative, Peleus prevented her from performing the experiment on Achilles.

Several episodes from his life, including the ambush of Troilus and the killing of Penthesilea, were popular with vase-painters (see pottery, greek). Also popular, in the later 6th cent., but with no known literary precedent, was a game of draughts (see games) between Achilles and Aias (1): a treatment by Execias (Vatican 16757 = ABV 145 = LIMC Achilleus 397, c.535–530 bce) is justly famous. In the 5th cent. he often appears as a beardless youth, for example on the name-vase of the Achilles-Painter (Vatican 16571 = ARV² 987 = LIMC Achilleus 907, c.450 bce), showing him alone as an ideal of male beauty.

Achilles had a tomb at Sigeum, where Alexander (3) the Great, among others, paid homage, and received cult honours in many places, in particular at Olbia and other sites on the north shore of the Black Sea (the region of the White Island, where he had a temple). This was more than a hero-cult as (in Roman times at least) he was honoured as a god, with the title Pontarches, Lord of the (Black) Sea (Alcaeus, fr. 354 L-P, addresses him as Lord of Scythia). The origin of this cult and its connection with the human Achilles of myth and epic are matters of debate.