1. The fabulous ancestor of the Ionians, is described as a son of Apollo by Creusa, the daughter of Erechtheus and wife of Xuthus. (Apollod. i. 7. § 3; CREUSA.) The most celebrated story about him is that which forms the subject of the Ion of Euripides. Apollo had visited Creusa in a cave below the Propylaea, and when she gave birth to a son, she exposed him in the same cave. The god, however, had the child conveyed to Delphi, and there had him educated by a priestess. When the boy had grown, and Xuthus and Creusa came to consult the oracle about the means of obtaining an heir, the answer was, that the first human being which Xuthus met on leaving the temple should be his son. Xuthus met Ion, and recognised him as his son; but Creusa, imagining him to be a son of her husband by a former beloved, caused a cup to be presented to the youth, which was filled with the poisonous blood of a dragon. However, her object was discovered, for as Ion, before drinking, poured out a libation to the gods, a pigeon which drank of it died on the spot. Creusa thereupon fled to the altar of the god. Ion dragged her away, and was on the point of killing her, when a priestess interfered, explained the mystery, and showed that Ion was the son of Creusa. Mother and son thus became reconciled, but Xuthus was not let into the secret. The latter, however, was satisfied, for he too received a promise that he should become a father, viz. of Dorus and Achaeus.
The inhabitants of Aegialus, on the northern coast of Peloponnesus, were likewise Ionians, and among them another tradition was current. Xuthus, when expelled from Thessaly, went to Aegialus. After his death Ion was on the point of marching against the Aegialeans, when their king Selinus gave him his daughter Helice in marriage. After the death of Selinus, Ion succeeded to the throne, and thus the Aegialeans received the name of Ionians, and the town of Helice was built in honour of Ion's wife. (Paus. vii. 1. § 2; Apollod. i. 7. § 2 ) Other traditions represent Ion as king of Athens between the reigns of Erechtheus and Cecrops; for it is said that his assistance was called in by the Athenians in their war with the Eleusinians, that he conquered Eumolpus, and then became king of Athens. He there became the father of four sons, Geleon, Aegicores, Argades, and Hoples, according to whom he divided the Athenians into four classes, which derived their names from his sons. After his death he was buried at Potamus. (Eurip. Ion, 578 ; Strab. viii. p. 383; Conon, Narrat. 27; comp. Herod. v. 66.)
2. [See IONIDES.]