Adrastus is mentioned as early as Homer's Iliad, and his story was (presumably) told in the Cyclic Thebaid.
He was said to be the founder of the Nemean Games, had hero cults at Sicyon, Megara, and Colonus, and was depicted in works of art from as early as the 6th century BC.
[22] While according to another, Adrastus fled to Sicyon after Amphiaraus killed Talaus, and got the throne by marrying Polybus' daughter.
He found a place to sleep, but soon after Tydeus, the exiled son of the Calydonian king Oeneus, also arrived seeking shelter, and the two began to fight over the same space.
When Adrastus discovered Polynices and Tydeus fighting like wild beasts (or in later accounts when he saw that Polynices wore the hyde of a lion and that Tydeus wore the Hyde of a Boar, or that they had those animals on their shields), he remembered an oracle of Apollo that said he should marry his daughters to a lion and a boar.
[31] Adrastus proceeded to assemble a large Argive army to attack Thebes, appointing seven champions to be its leaders.
One of those chosen, the seer Amphiaraus, had foreseen that the expedition was doomed to fail, and that all of the champions but Adrastus would die, and so refused to join.
Athenian tradition held that Theseus, the king and founder-hero of Athens, assisted Adrastus in recovering the bodies of his fallen comrades.
[40] This time (according to Pindar) the omens foretold success for the expedition, but death for Adrastus' son Aegialeus.
[42] According to Pausanias, the Megarians said that Adrastus, leading the Argive army home after taking Thebes, died at Megara of old age and grief for the death of his son, and was honored there.
[48] The lyric poet Stesichorus (c. 630 – 555 BC) apparently wrote a poem (now lost) about the war against Thebes,[49] in which Adrastus would presumably have figured.
[61] And, after the death of Amphiaraus, Pindar has Adrastus say: "I dearly miss the eye of my army, good both as a seer and at fighting with the spear.
"[62] In Pythian 8, Pindar mentions Ardastus receiving a prophecy from the dead Amphiaraus during the battle of the Epigoni at Thebes:[63] Adrastus is a principal character in Euripides' tragedy The Suppliants (c. 420 BC).
[64] The action of the play takes place after the disastrous defeat of the Seven against Thebes, and the refusal of Creon, the new Theban king, to allow the burial of the expedition's dead.
[65] In an initial interview, Adrastus tells Theseus, the king of Athens, that because of an oracle of Apollo, he had given his daughters (unnamed) to Polynices and Theseus, and that, because of the "crime" done to Polynices by his brother Eteocles, who had stolen "his property" (i.e. the Theban throne), Adrastus marched "seven companies against Thebes".
As in Euripides, because of an oracle, Adrastus married his daughters Argia to Polynices and Deipyle to Tydeus, and promised to restore the exiles to their native kingdoms.
But Polynices gave Amphiaraus's wife Eriphyle the necklace of Harmonia, so that she would persuade her husband to join the expedition.
[71] Adrastus recruited Capaneus, Hippomedon and Parthenopaeus, the son of Atalanta, to join himself, Polynices, Tydeus, and Amphiaraus as the seven leaders of the "notable army", the same list of Seven as in Euripides' The Phoenician Women.
As for the burial of the Seven, Diodorus (with no mention of Creon or Theseus) says that the Thebans refused to allow Adrastus to remove the dead, so he went home to Argos, and (as in Euripides' The Suppliants) the Athenians recovered the bodies and buried them.
[89] In Book 3, on returning to Argos, the wounded Tydeus urges an immediate attack of Thebes, an action the angry crowd supports.
[93] Amphiaraus is finally forced to reveal what he has foreseen: death and defeat at Thebes, but the Argives are undeterred.
[94] Argia, now Polynices' wife, tearfully urges her father Adrastus to make war on Thebes, who begins assembling an army.
[99] The Archive champions rush to defend Hypsipyle—their army's savior—and Nemeans rally to their king, but Adrastus and Amphiaraus intercede, preventing an armed clash.
Adrastus promised to restore both his son-in-laws to their kingdoms, and "eager to march against Thebes" first, began to assembled an army.
So, when Polynices bribed Amphiaraus' wife Eriphyle to tell her husband to join the expedition, he was forced to obey.
However, as Apollodorus notes, some do not count Polynices and Tydeus as being among the seven, instead including Eteoclus, son of Iphis, and Mecisteus (another brother of Adrastus) in the list of the seven.
A Chalcidian calyx krater (c. 530 BC) depicts the arrival scene of the exiled princes Polynices and Tydeus at Adrastus' palace.
They are both looking to the left where Tydeus (also named) and another man (presumed to be Polynices) are sitting on the ground with their mantles wrapped around them, with two women conversing standing over them (Adrastus' daughters?).
[118] Pausanias reports seeing Adrastus depicted on the Amyclae Throne of Apollo (6th century BC), along with Tydeus, stopping a fight between Amphiaraus and "Lycurgus the son of Pronax".
[123] A line in Virgil's Aeneid has Aeneas, in the underworld, encounter "the pale shade of Adrastus" (Adrasti pallentis imago).