Aethlius (Ancient Greek: Ἀέθλιος, meaning "winning the prize"), also called Aithlios or Aethnos, was the first king of Elis in Greek mythology. He was the son of Zeus and Protogeneia, the daughter of Deucalion, and married Calyce, by whom he fathered Endymion. He is said to have led Aeolian settlers from Thessaly to found Elis, and his name was traditionally linked to the origin of the word "athletes."
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I.Etymology
The name Aethlius (Ancient Greek: Ἀέθλιος), also rendered Aithlios, is glossed as meaning "winning the prize." An alternative form of the name, Aethnos, is also attested.
According to the tradition reported by Eusebius, it was from the name of Aethlius that contestants and adversaries came to be called "athletes."
II.Family
Aethlius was the son of Zeus and Protogeneia, the daughter of Deucalion, and he married Calyce, by whom he fathered Endymion.
Accounts of his place in the lineage vary. Some traditions identify Endymion himself as a son of Zeus and as the first king of Elis. Other accounts describe Aethlius instead as a son of Aeolus, who was given the name of Zeus.
III.Mythology
Aethlius led the Aeolians from Thessaly and founded Elis.
According to Eusebius, as a means of challenging his sons, Aethlius drew on the concept of the Olympic games of the Idaean Dactyls, and it was from his name that contestants came to be called athletes.
After Aethlius, his sons Epeius and then Endymion, Alexinus, and Oenomaus were each in turn placed in charge of the sacrifices connected with the festival.