Creusa, daughter of Erechtheus, was a noble native of Athens. The god Apollo seduced her in a cave; there she gave birth to his son and intended to kill him by exposure. She keeps all this a secret. Many years later she was near the end of child bearing age, and had so far been unable to have a child with her husband Xuthus, a Thessalian and son of Aeolus. So they traveled to Delphi to seek a sign from the oracles.
Ion is an ancient Greek play by Euripides, thought to be written between 414 and 412 BC. It follows the orphan Ion in the discovery of his origins.
Atlas, that on his brazen shoulders rolls
Yon heaven, the ancient mansion of the gods,
Was by a goddess sire to Maia; she
To supreme Jove bore me, and call'd me Hermes;
Attendant on the king, his high behests
I execute. To Delphi am I come,
This land where Phoebus from his central throne
Utters to mortals his high strain, declaring
The present and the future; this is the cause;
Greece hath a city of distinguish'd glory,
Which from the goddess of the golden lance
Received its name; Erechtheus was its king;
His daughter, call'd Creusa, to the embrace
Of nuptial love Apollo strain'd perforce,
Where northward points the rock beneath the heights
Crown'd with the Athenian citadel of Pallas,
Call'd Macrai by the lords of Attica.