In ancient Greek religion, chief deity of the pantheon, a sky and weather god who was identical with the Roman god Jupiter
(q.v.). Zeus was regarded as the sender of thunder and lightning, rain, and winds, and his traditional weapon was the thunderbolt. He was called the father (i.e., the ruler and protector) of both gods and men.
According to a Cretan myth that was later adopted by the Greeks, Cronus, king of the Titans, upon learning that one of his children was fated to dethrone him, swallowed his children as soon as they were born. But Rhea, his wife, saved the infant Zeus by substituting a stone wrapped in swaddling clothes for Cronus to swallow and hiding Zeus in a cave on Crete. There he was nursed by the nymph (or female goat) Amalthaea and guarded by the Curetes (young warriors), who clashed their weapons to disguise the baby’s cries. After Zeus grew to manhood he led a revolt against the Titans and succeeded in dethroning Cronus, perhaps with the assistance of his brothers Hades and Poseidon, with whom he then divided dominion over the world.
As ruler of heaven Zeus led the gods to victory against the Giants (offspring of Gaea and Tartarus) and successfully crushed several revolts against him by his fellow gods. According to the Greek poet Homer, heaven was located on the summit of Olympus, the highest mountain in Greece and the logical home for a weather god. The other members of the pantheon resided there with Zeus and were subject to his will. From his exalted position atop Mount Olympus Zeus was thought to omnisciently observe the affairs of men, seeing everything, governing all, and rewarding good conduct and punishing evil. Besides dispensing justice, Zeus was the protector of cities, the home, property, strangers, guests, and supplicants.
Zeus was well known for his amorousness—a source of perpetual discord with his wife, Hera—and he had many love affairs with both mortal and immortal women. In order to achieve his amorous designs, Zeus frequently assumed animal forms, such as that of a cuckoo when he ravished Hera, a swan when he ravished Leda, or a bull when he carried off Europa. Notable among his offspring were the twins Apollo and Artemis, by the Titaness Leto; Helen and the Dioscuri, by Leda of Sparta; Persephone, by the goddess Demeter; Athena, born from his head after he had swallowed the Titaness Metis; Hephaestus, Hebe, Ares, and Eileithyia, by his wife, Hera; Dionysus, by the goddess Semele; and many others.
In art Zeus was represented as a bearded, dignified, and mature man of stalwart build; his most prominent symbols were the thunderbolt and the eagle.
Throughout Italy Jupiter was worshiped on the summits of hills; thus, on the Alban Hill south of Rome was an ancient seat of his worship as Jupiter Latiaris, which was the centre of the league of 30 Latin cities of which Rome was originally an ordinary member. At Rome itself on the Capitoline Hill was his oldest temple; here there was a tradition of his sacred tree, the oak, common to the worship both of Zeus and of Jupiter, and here, too, were kept the lapides silices, pebbles or flint stones, which were used in symbolic ceremonies by the fetiales, the Roman priests who officially declared war or made treaties on behalf of the Roman state.
Jupiter was not only the great protecting deity of the race but also one whose worship embodied a distinct moral conception. He is especially concerned with oaths, treaties, and leagues, and it was in the presence of his priest that the most ancient and sacred form of marriage (confarreatio) took place. The lesser deities Dius Fidius and Fides were, perhaps, originally identical and certainly were connected with him. This connection with the conscience, with the sense of obligation and right dealing, was never quite lost throughout Roman history. In Virgil’s Aeneid, though Jupiter is in many ways as much Greek as Roman, he is still the great protecting deity who keeps the hero in the path of duty (pietas) toward gods, state, and family.
But this aspect of Jupiter gained a new force and meaning at the close of the early Roman monarchy with the building of the famous temple on the Capitol, of which the foundations are still to be seen. It was dedicated to Iuppiter Optimus Maximus (i.e., the best and greatest of all the Jupiters), and with him were associated Juno and Minerva, in a fashion that clearly indicates a Greco-Etruscan origin, since the combination of three deities in one temple was foreign to the ancient Roman religion, while it is found in both Greece and Etruria. The temple’s dedication festival fell on September 13, on which day the consuls originally succeeded to office, accompanied by the Senate and other magistrates and priests. In fulfillment of a vow made by their predecessors, the consuls offered to Jupiter a white ox, his favourite sacrifice, and, after rendering thanks for the preservation of the state during the past year, they made the same vow as that by which their predecessors had been bound. Then followed the feast of Jupiter. In later times this day became the central point of the great Roman games. When a victorious army returned home the triumphal procession passed to this temple.