In Greek mythology, Achilles was a Greek hero of the Trojan War and the central character and greatest warrior of Homer's Iliad. His mother was the immortal nereid Thetis, and his father, the mortal Peleus, was the king of the Myrmidons.
Achilles' most notable feat during the Trojan War was the slaying of the Trojan hero Hector outside the gates of Troy. Although the death of Achilles is not presented in the Iliad, other sources concur that he was killed near the end of the Trojan War by Paris, who shot him in the heel with an arrow. Later legends (beginning with a poem by Statius in the 1st century AD) state that Achilles was invulnerable in all of his body except for his heel because, when his mother Thetis dipped him in the river Styx as an infant, she held him by one of his heels. Alluding to these legends, the term "Achilles heel" has come to mean a point of weakness, especially in someone or something with an otherwise strong constitution.
During the first nine years of the war, Achilles ravaged the country around Troy and took 12 cities. In the 10th year a quarrel with Agamemnon occurred when Achilles insisted that Agamemnon restore Chryseis, his prize of war, to her father, a priest of Apollo, so as to appease the wrath of Apollo, who had decimated the camp with a pestilence. An irate Agamemnon recouped his loss by depriving Achilles of his favourite slave, Briseis.
Achilles refused further service, and consequently the Greeks floundered so badly that at last Achilles allowed Patroclus to impersonate him, lending him his chariot and armour. Hector (the eldest son of King Priam of Troy) slew Patroclus, and Achilles, having finally reconciled with Agamemnon, obtained new armour from the god Hephaestus and slew Hector. After dragging Hector’s body behind his chariot, Achilles gave it to Priam at his earnest entreaty. The Iliad concludes with the funeral rites of Hector. It makes no mention of the death of Achilles, though the Odyssey mentions his funeral. The poet Arctinus in his Aethiopis took up the story of the Iliad and related that Achilles, having slain the Ethiopian king Memnon and the Amazon Penthesilea, was himself slain in battle by Priam’s son Paris, whose arrow was guided by Apollo.