Diomedes (Ancient Greek: Διομήδης; transliteration Diomēdēs; transl. "divine cunning" or "advised by Zeus") is, in Greek mythology, the son of Tideus, prince of Argos before and after the reign of Agamemnon (because he was the only hero of the city-state, he received the title of prince) and the bravest Greek hero in the Trojan War, only after Achilles.
He was helped by Athena, wounded the goddess Aphrodite and also the god Ares who complains to Zeus about Diomedes' boldness.
He is the son of Tideus with Deipile, one of the daughters of Adrasto, king of Argos. Diomedes was one of the epigones.
He was also one of Helen's prented and is Odysseus' usual companion. It is the two of them who kill Dolon, a Trojan spy.
Upon returning to Argos, Egialeia, his wife, betrays him by setting several traps in an attempt to kill him, he then flees to the court of King Dauno, in which the host gives his daughter's hand in marriage to Diomedes.
In Ovid's version, Diomedes in Italy married the daughter of King Dauno. When Venulus, Aeneas' companion, asked for help in men, Diomedes denied, justifying it with the story that his men had been turned into birds.
In the story, told by Diomedes to Venulus, he, like the rest of the Greeks, did not have an easy return to his hometown Argos, and arrived safely with the help of Minerva, but Venus decided to take revenge on him, for he had injured her, and he, with his companions, set out from Argos.
During the journey, his companions complained to the goddess and defied her, saying that she could no longer do anything against them, but they were turned into birds.
Diomedes in the Iliad
The Iliad presents Diomedes as, in Achilles' absence, the greatest Achaean fighter, alongside Agax Telamonius, the latter defending his companions and the other attacking the Trojans.