Ganymede was born to Tros, the king of Troy and the eponym of the Trojans, and Callirhoe, the daughter of Scamander, the river-god whose waters flowed through the plain where the city stood. From his earliest youth, he was renowned as the most beautiful of all mortals, a beauty so radiant that it drew the eye of Zeus himself. Homer, the poet of the Iliad, says that the gods caught him up because of his beauty, so that he might dwell among the immortals and pour wine for them at their eternal feasts. He was hunting on the slopes of Mount Ida when the eagle came.

The defining moment of Ganymede's life came on a day like any other. The youth was among his companions on Mount Ida, perhaps hunting with his hounds or exercising his father's horses, when a great eagle descended from the clouds. Some said it was Zeus himself in the form of the bird, his golden wings blotting out the sun; others said it was the eagle Aquila, sent by the god to fetch the boy. The bird seized Ganymede in its talons and bore him up through the sky to the high throne-room of Olympus. His companions cried out and searched the mountain for him, but the eagle had already vanished into the realm of the gods, and Ganymede was gone from the earth forever.

On Olympus, Ganymede was given a new role. Hebe, the daughter of Zeus and Hera, the queen of the gods, had served as the cupbearer of the immortals, pouring nectar and ambrosia at the divine banquets. Ganymede took her place, standing beside the golden throne of Zeus and filling the cups of the gods with the wine of immortality. He was granted eternal youth and a place among the stars as the constellation Aquarius, the Water-Bearer, whose jar pours the winter rains upon the earth. Homer says that the gods rejoiced in him, and that Zeus was so pleased with his service that he gave Tros, the boy's father, a pair of divine horses as compensation for the loss of his son.

Not all the gods welcomed the new cupbearer. Hera, the wife of Zeus, was said to resent the beautiful Trojan youth who had displaced her daughter Hebe from her honoured position. Some later poets hinted at darker tensions on Olympus, suggesting that Ganymede's presence was a constant reminder of Zeus's wandering eye. Yet in the earliest Greek tradition, the abduction was not portrayed as a tragedy but as an elevation, a mortal raised to the divine sphere by the supreme god's favour. The Homeric Hymn to Aphrodite mentions Ganymede as one of the few mortals whom the gods loved so dearly that they granted him immortality, placing him alongside Tithonus in the select company of those who escaped death.

In later ages, the image of Ganymede and the eagle became one of the most enduring motifs in Western art. The Greeks painted it on hundreds of vases, showing the eagle descending or the youth riding upon its back. The Romans adopted the scene with enthusiasm, and in the Renaissance it was painted by Michelangelo, Correggio, and Rubens, each interpreting the abduction as a moment of divine rapture or earthly violence. The name Ganymede passed into Latin as Catamitus, which became the English word catamite, carrying the memory of the Trojan prince into modern discourse. The largest moon of Jupiter, discovered by Galileo in 1610, bears his name, a fitting tribute to the youth who served the king of the gods.