Many of the gods and goddesses of Greek mythology were related to each other through marriage, shared parentage or both, with almost all of them being connected to Zeus. The 12 major deities of ancient Greek religion, also known as the pantheon, consisted of Zeus, Hera, Poseidon, Demeter, Athena, Apollo, Artemis, Hermes, Hephaestus, Dionysus, Ares and Aphrodite, and they were all members of the same family.
Zeus, the god of thunder and lightning, was the reigning patriarch of the family of Greek gods and goddesses. He was the youngest son of the titans Kronos and Rhea, and his siblings included Poseidon, the god of the sea, and Hades, the lord of the underworld, along with the goddesses Hera, Demeter and Hestia. Zeus married Hera, the goddess of birth and marriage. Their children included Ares, the god of war; Hephaestus, the god of metalworking; and Hebe, the goddess of youth.
Zeus also fathered several of the other gods and goddesses through unions outside of his marriage. His affair with a woman named Leto produced the twin deities Apollo and Artemis. Apollo was the god of music, poetry and archery, while his sister Artemis ruled over the hunt. The goddess of love and beauty, Aphrodite, also claimed Zeus as her father, although this is disputed in some stories.
While the Greek god of wine, Dionysus, and the messenger god, Hermes, each had different mothers, they were both sons of Zeus as well. The thunder god also gave birth to the goddess of wisdom, Athena, who climbed out of Zeus' head fully formed after he endured a pounding headahce for several days.