Megara was Hercules’ mortal wife before Deianira.
Megara was the daughter of Creon, king of Thebes, and she married Hercules in stories set before or around the beginning of his labors. Their marriage ended in tragedy when Hera caused Hercules to fall into a fit of madness. In that state, he killed his children and, in some versions, Megara as well.
The crime led Hercules to seek purification and punishment. Eurystheus then assigned the series of difficult tasks that became the Twelve Labors. Details vary between ancient authors, especially concerning whether Megara survived the attack and what happened to her afterward.
Megara should not be confused with Deianira, whom Hercules married later. Deianira is connected with the centaur Nessus and the poisoned shirt, while Megara belongs to the family tragedy that explains why Hercules entered Eurystheus’ service.