Hera was the queen of Olympus, wife of Zeus, and deity associated with family, women, and children. But Hera and Zeus didn't have the most harmonious of marriages. In fact, Zeus tricked Hera into marrying him, kicking off a lifetime of infidelity and revenge stories involving the mythological couple.
Hera was best known in ancient Greek mythology stories for her vengeful acts against Zeus's many lovers. In her defense, though, Zeus was notorious for having relations with just about every woman in Ancient Greece, goddess and mortal alike.
But for all the times Zeus cheated on Hera, the goddess of marriage had a myriad of wrathful responses. From sending the many-headed Hydra to slay Zeus's illegitimate son Hercules to cursing Echo to forever mimic the conversations of others, Hera's revenge was swift and severe.
The Titan Leto was the first object of Zeus's many extramarital desires. Hera promised to curse any land that harbored Leto while she was pregnant with Zeus's children Apollo and Artemis. Leto was forced to wander for months seeking refuge.
Even when she finally settled in Delos to give birth, Hera forced the goddess of childbirth and Hera's daughter, Ilithyia, to make Leto's labor last for nine whole months.
Among the many attempts to take revenge upon Zeus, Alcmene, and their son Heracles (better known as Hercules), Hera once caused the young demigod to go insane. During Hercules's frenzy of confusion and anger, he slew his wife and their two children, but his insanity was only temporary. When he awoke from it, he realized what he had done.
This horrible experience caused Hercules, in his anguish and guilt, to seek counsel from Apollo and undertake the famous 12 heroic labors.
Zeus took another lover, the mortal Semele, after he saw her sacrifice a bull in his honor. Zeus visited Semele often and she became pregnant. Hera discovered Zeus's infidelity, worked to befriend Semele, and tricked her into asking Zeus to show himself in all his glory, knowing that mortals cannot look upon the gods.
Zeus had made a promise to grant Semele whatever she wished, so he obliged; Semele burst into flames as a result.
Alcmene, daughter of Electryon, was betrothed to Amphitryon and intended to have a son with him, but Amphitryon was exiled from their homeland for accidentally slaying King Electyron. The two went to Thebes with the intention of getting their kingdom back. When Amphitryon left on a campaign, Zeus disguised himself as Alcmene's husband and tricked her into bed. Upon finding out Zeus was the father of forthcoming baby Hercules, Hera was not happy.
Zeus said his son would inherit the Mycenaean kingdom, but Hera had other designs. Hera convinced the goddess of childbirth, Ilythia, to sit cross-legged, preventing Hercules's birth. But after a week or two, one of Alcmene's servants tricked Ilithyia into opening her legs, thwarting Hera's plan. In the meantime, Hercules's cousin Eurystheus was born and inherited the Mycenaean kingdom.
After seeing to it that Hercules did not inherit the Mycenaean kingdom as Zeus had promised, Hera sent two snakes to slay the infant Hercules while he slept in his crib. Again, her plan didn't succeed, as the baby was incredibly strong and dispatched the snakes before they could harm him. This incident confirmed that Hercules was part god, only enraging Hera further.