Seven wives of Zeus
According to Hesiod, Zeus had seven wives. His first wife was the Oceanid Metis, whom he swallowed on the advice of Gaia and Uranus, so that no son of his by Metis would overthrow him, as had been foretold. Later, their daughter Athena would be born from the forehead of Zeus.
Hera. The most famous wife of Zeus is Hera. She was his principal wife and the Queen of heaven.
Zeus finally became enamored of the goddess who was to become his permanent wife — Hera. After courting her unsuccessfully he changed himself into a disheveled cuckoo. When Hera took pity on the bird and held it to her breast, Zeus resumed his true form and ravished her.
Zeus fell in love with Io and seduced her. To try to keep Hera from noticing he covered the world with a thick blanket of clouds. This backfired, arousing Hera's suspicions. She came down from Mount Olympus and begain dispersing the clouds.
Metis, an Oceanid or sea-nymph, was Zeus's first wife. Wise and prudent, she was endowed with the gift of prophecy. In their early years together, she was Zeus's closest ally and aide, helping him win the battle against Cronus.
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Aphrodite later and of her own volition had an affair with Zeus, but his jealous wife Hera laid her hands upon the belly of the goddess and cursed their offspring with malformity. Their child was the ugly god Priapos.
Impregnation by Zeus
Nonnus classifies Zeus's affair with Semele as one in a set of twelve, the other eleven women on whom he begot children being Io, Europa, Plouto, Danaë, Aigina, Antiope, Leda, Dia, Alcmene, Laodameia, the mother of Sarpedon, and Olympias.
Perhaps partly because of the strange circumstances of her birth, Athena is often cited as Zeus's favourite child. He also greatly admired her strength of character and fighting spirit. Some believe Athena was Zeus's first born child, which might, somewhat unfairly, suggest why he chose her as his favourite.
After Zeus became king, he and Metis were married, and she bore him a daughter, Athena, the goddess of wisdom. After hearing a prophecy stating that after Metis gave birth to Athena, she would have a son mightier than Zeus who would overthrow him, Zeus tricked the still pregnant Metis and swallowed her whole.
Ganymede (or Ganymedes) was a young man from Troy. His beauty was unparalleled and for that reason, Zeus abducted and brought him to Olympus to serve as his cupbearer and lover. Ganymede's myth is an important step in the history of homosexuality.
Hera was worshipped throughout the Greek world and played an important part in Greek literature, appearing most frequently as the jealous and rancorous wife of Zeus and pursuing with vindictive hatred the heroines who were beloved by him.
Zeus and Metis
His first and favorite lover was Metis, a Titan goddess and mother of Athena.
According to the Orphic myths, Zeus wanted to marry his mother Rhea. After Rhea refused to marry him, Zeus turned into a snake and raped her. She had Persephone with Zeus.
In some versions of Greek mythology, Zeus ate his wife Metis because it was known that their second child would be more powerful than him. After Metis's demise, their first child Athena was born when Hephaestus cleaved Zeus's head open and the goddess of war emerged, fully grown and armed.
Suffice it to say that Zeus was constantly involved in extramarital affairs. Throughout the various and sometimes contradictory myths composed by Greek authors, there are at least 20 divine figures with whom he consorted, and about twice as many mortals.
Why is Zeus married to his sister? To hide her shame, Hera agreed to marry him. It was a violent marriage at best. Though Zeus had pursued his sister and sought to possess her by marriage, he never gave up his lusty ways.
Metis. Metis was the first wife of Zeus, and one of the Titans, a daughter of Oceanus and Tethys.
Under the name of Callithyia, Io was regarded as the first priestess of Hera, the wife of Zeus. Zeus fell in love with her and, to protect her from the wrath of Hera, changed her into a white heifer. Hera persuaded Zeus to give her the heifer and sent Argus Panoptes (“the All-Seeing”) to watch her.
Zeus slept with his own daughter, Persephone, because she was there.
In his private life Zeus was quite the lothario, fathering an unbelievable number of around 100 children with many different women (but don't hate him too much – it's just a myth, after all). Of this 100, he fathered a mix of sons and daughters, many of whom were gods and goddesses, and some became great leaders.
According to many versions of the story, Zeus took the form of a swan and had sexual intercourse with Leda on the same night she slept with her husband King Tyndareus. In some versions, she laid two eggs from which the children hatched.
Athena (Minerva), the goddess of war and wisdom, had a strange birth. Her father Zeus (Jupiter) had swallowed his pregnant consort Metis (“wisdom”), because he was afraid she would bear a son who would overthrow him.
Zeus and Hera play important roles in Greek mythology. Zeus is the Greek god of the skies, and Hera is the Greek goddess of marriage and birth. Hera is also known as Queen of the Gods because of her matriarchal role in Greek mythology. Together, Zeus and Hera had three children: Ares, Hebe, and Hephaestus.
Mnemosyne spent nine nights with Zeus, and on each of these nights, he fathered a child. The nine children were born in the same birth and were known as the nine muses, the goddesses of artistic inspiration. The nine daughters of Mnemosyne and Zeus were: Calliope, muse of epic poetry.