Iolaus

In Greek mythology, Iolaus (Greek: Ἰόλαος Iólaos) was a Theban divine hero, son of Iphicles and Automedusa.

He was famed for being Heracles's nephew and for helping with some of his Labors, and also for being one of the Argonauts. Through his daughter Leipephilene, he was considered to have fathered the mythic and historic line of the kings of Corinth, ending with Telestes.

A genus of Lycaenid butterfly has been named after him.

As a son of Iphicles, Iolaus was a nephew of Heracles. He often acted as Heracles' charioteer and companion. He was popularly regarded as Heracles's lover, and the shrine to him in Thebes was a place where male couples worshiped and made vows.

The Theban gymnasium was also named after him, and the Iolaia or Iolaea (Greek: Ιολάεια), an athletic festival consisting of gymnastic and equestrian events, was held yearly in Thebes in his honor. The victors at the Iolaea were crowned with garlands of myrtle.

Iolaus provided essential help to Heracles in his battle against the Hydra, his second labor. Seeing that Heracles was being overwhelmed by the multi-headed monster (the Lernaean Hydra), who grew two heads in place of each one cut off, Iolaus sprang to help, cauterizing each neck as Heracles beheaded it.

Heracles gave his wife, Megara, age thirty three, to Iolaus, then only sixteen years old – ostensibly because the sight of her reminded him of his murder of their three children. They had a daughter, Leipephilene. He was one of the Heraclidae.

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