Meleager was born in Calydon, the chief city of Aetolia in western Greece, the son of King Oeneus and Queen Althaea. His father was a descendant of the wine-god Dionysus, and his mother was the daughter of Thestius, the king of Pleuron, making Meleager a prince of two royal houses. On the night of his birth, the three Fates, the Moirai who spin the thread of every mortal life, appeared in Althaea's chamber and declared his destiny. Clotho, the spinner, drew the thread of his life from her distaff. Lachesis, the allotter, measured its length upon her rod. And Atropos, the cutter, took a brand from the fire and said: "This child shall live only as long as this brand remains unconsumed by flame." Althaea snatched the brand from the goddess's hand and hid it in a chest, guarding it as the most precious thing she possessed, for as long as the wood remained whole, her son would live.

Meleager grew to manhood in a kingdom famous for its hunting and its horses. He was strong, swift, and skilled with every weapon, and his fame spread across Greece until he was counted among the greatest heroes of his generation. He sailed with the Argonauts, the crew of the ship Argo who sought the Golden Fleece in the distant land of Colchis on the Black Sea, and he fought alongside Jason, Peleus, and the other champions who would one day send their sons to Troy. But the event that defined his life began not with his own choice but with his father's negligence.

Oeneus, in offering the first fruits of the harvest to the gods, had forgotten Artemis, the virgin goddess of the hunt, whose province was the wild places and the animals that lived in them. The omission was not deliberate malice but simple oversight, yet Artemis was not a goddess who forgave insults. She sent a boar to ravage the fields of Calydon, a creature of monstrous size whose tusks were longer than a man's arm, whose breath was fire, and whose hide was so thick that no ordinary spear could pierce it. The boar destroyed vineyards, orchards, and cattle, and the people of Calydon fled to the city walls in terror. Oeneus called upon the heroes of Greece to hunt the beast, and Meleager, though the hunt was in his own kingdom, knew that he needed help.

He sent messengers across the Greek world, and the greatest heroes answered his call. Jason came, the leader of the Argonauts. Peleus came, the father of Achilles, the greatest warrior of the Trojan War. Theseus came, the slayer of the Minotaur, the monster who dwelt in the labyrinth of Crete. Castor and Polydeuces, the twin brothers known as the Dioscuri, came with their horses. And Atalanta came, the daughter of Schoeneus, the huntress raised by a she-bear, the fastest runner and the most accurate archer in all Greece. Meleager fell in love with her at first sight, and his love would cost him everything.

The hunt was terrible. The boar charged from its lair in a marsh beside the river Evenus, and the heroes scattered before its fury. Several were killed, gored by the great tusks or trampled beneath its hooves. Atalanta, the only woman in the company, was the first to wound it, shooting an arrow that struck the beast behind the ear. Meleager, seeing his chance, drove his spear into the boar's flank and finished it with a sword-thrust to the heart. The monster fell, and the heroes cheered, but the quarrel over the spoils began before the blood had dried.

Meleager stripped the hide from the boar and presented it to Atalanta, declaring that she had drawn first blood and deserved the trophy. His uncles, Althaea's brothers Plexippus and Toxeus, objected violently. They were Aetolian nobles, they said, and the hide of a beast killed in Aetolia belonged to Aetolian men, not to a foreign woman. Meleager refused to yield. The argument became a fight, and in his rage Meleager killed both his uncles, striking them down with the same spear that had slain the boar. He gave the hide to Atalanta, and she accepted it, but the gift was poisoned by the blood of his mother's brothers.

When Althaea learned that her son had killed her brothers, her grief turned to fury. She took the brand from the chest where she had hidden it for twenty years, the piece of wood that held her son's life, and she placed it in the fire. Meleager, still celebrating the hunt, felt a sudden burning in his chest, as if the fire were inside him. He collapsed, and his life drained away as the brand turned to ash in his mother's hands. Some accounts say that Althaea, realising what she had done, threw herself into the fire and died with her son. Others say that she hanged herself in remorse. In every version, the mother who had saved her son's life at birth destroyed it in adulthood, and the brand that had been his protection became his execution.

Meleager's death was mourned by his sisters, the Meleagrids, who wept so inconsolably that the gods took pity on them and transformed them into guinea fowl, the birds whose spotted plumage was said to resemble the tears that fell upon their brother's tomb. The tomb itself stood on the banks of the river Evenus, and the people of Calydon offered sacrifices there every year, honouring the hero who had saved their city and died for his love of a huntress.