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— CH. 1 · INTRODUCTION —

Jupiter (god)

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  • Jupiter, king of the Roman gods, takes his name from two ancient words: the Proto-Italic djous, meaning "day" or "sky," and pater, meaning "father." Sky Father. The name alone tells you what the Romans believed they were dealing with. For most of the Republican and Imperial eras, Jupiter stood as the chief deity of Roman state religion, holding that position until Christianity reshaped the empire. His symbol was the thunderbolt. His sacred animal was the eagle. Together those two emblems appeared on coins across the known world, fused into a single image of an eagle gripping a lightning bolt in its claws. But Jupiter was far more than a storm deity. He was the source of the auspices on which Rome's relationship with the gods rested, the witness to every oath, the guarantor of justice, and the divine anchor of Roman sovereignty itself. How did one god come to bear so much weight? What did his priests eat, wear, and forbid themselves to touch? How did ordinary Romans plead with him during times of crisis? And how did a deity born in the ancient Latin hills eventually travel to the site of the destroyed Temple in Jerusalem, to the Great St Bernard Pass in the Alps, and to the banks of the Danube? The answers stretch across mythology, politics, and daily religious practice in ways that still leave traces in the languages spoken across Europe today.

  • The consuls of Rome swore their oath of office in Jupiter's name. Every year, on the annual feriae of the Capitol in September, they honoured him with a sacrifice of a white ox with gilded horns. The choice of animal was precise: white, male, with horns coated in gold. This was not devotion for its own sake. The Romans believed Jupiter had granted them supremacy over other peoples because they had honoured him more faithfully than anyone else had. He personified, in the words scholars draw from the ancient sources, "the fount of the auspices upon which the relationship of the city with the gods rested." Triumphal generals made a similar offering after military victories. They surrendered the tokens of their victory at the feet of Jupiter's statue in the Capitol, and some scholars read in this ritual an act of impersonation: the triumphator embodying Jupiter himself during the procession. When Jupiter's authority and the ambitions of individual Romans came into conflict, the god won. In the 5th century BC, the triumphator Camillus was sent into exile after he drove a quadriga of four white horses, an honour reserved for Jupiter alone. Marcus Manlius, who had earned the name Capitolinus for defending the Capitol against an invasion by the Gauls, was later accused of harbouring kingly ambitions. He was cast from the Tarpeian Rock, his house on the Capitoline Hill was razed, and a decree forbade any patrician from ever living on that spot again. Capitoline Jupiter, and the power he conferred on magistrates, was not to be competed with. The Temple of Jupiter Optimus Maximus on the Capitoline Hill, begun under Tarquinius Priscus and inaugurated on the 13th of September 509 BC, became the architectural model for his provincial temples across the empire. Its roof bore statues of four horses drawing a quadriga, with Jupiter as charioteer. Inside, on festival days, the face of his large statue was painted red. Within or near the temple stood the Iuppiter Lapis, a stone on which the most solemn oaths in Roman life could be sworn.

  • The Flamen Dialis, the high priest of Jupiter, ranked above all fifteen priests in the official public cult of Rome. His wife, the Flaminica Dialis, held duties of her own: she sacrificed a ram to Jupiter on each of the nundinae, the market days that divided the Roman calendar into its recurring nine-day cycle. The couple were required to marry through the exclusively patrician ritual of confarreatio, a ceremony that included a sacrifice of spelt bread to Jupiter Farreus. Spelt, the grain, gave this form of Jupiter his name. The rules governing the Flamen Dialis were unlike those of any other Roman priest. He could remove his clothing or his pointed hat, the apex, only while under a roof, so that he would not expose himself naked to the sky under the eyes of Jupiter. Every time his wife saw a lightning bolt or heard thunder, she was prohibited from continuing her normal routine until she had placated the god. The flamen alone among priests was preceded by a lictor and held a seat in the Roman Senate. He had the use of the curule chair. But he was forbidden to ride a horse, and he could not see the army outside the sacred boundary of Rome, the pomerium. Though he served a god who embodied the sanctity of oaths, the Flamen Dialis himself could not swear one. He was barred from contact with anything connected with death: corpses, funerals, funeral fires, or raw meat. These restrictions were understood to reflect Jupiter's own nature, a nature defined by the fullness of life and absolute freedom. The Flaminica Dialis wore a garment dyed with pomegranate rind, carried a small rod, and kept her hair bound with purple ribbons. The office of Flamen Dialis had, at certain periods, gone unfilled for years at a stretch because the requirements were considered almost impossible to meet. The high priesthood of Jupiter, unlike other major religious offices, never became available to plebeians. It remained the preserve of the patrician class throughout the Republic.

  • Rome's class struggle, the centuries-long Conflict of the Orders between patricians and plebeians, played out partly as a theological dispute about who had Jupiter's backing. Patricians held the state auspices and could claim the supreme god supported them on that basis alone. Plebeians countered that Jupiter was the source of justice, and their cause was just, so his favour was theirs. The first secessio began over debt. The legal device known as the nexum allowed a debtor to become the effective slave of his creditor. When the senate refused to accept the proposal for a total debt remission put forward by the dictator and augur Manius Valerius Maximus, the plebs withdrew to the Mons Sacer, a hill three Roman miles northeast of Rome on the far side of the Nomentan bridge over the river Anio. The place was windswept and associated with divination performed by haruspices. The senate eventually dispatched a ten-member delegation that included Menenius Agrippa and Manius Valerius with authority to negotiate. According to an inscription found at Arezzo in 1688, erected by order of Augustus, it was Valerius who persuaded the secessionists to descend from the hill. Before they came down, they had consecrated the Mons Sacer to Jupiter Territor and built an altar on its summit. The fear of Jupiter's wrath was, by the ancient accounts, a real factor in resolving the standoff. The second secession arose from the conduct of the decemviri, a body charged by the Roman people with publishing all existing laws, which until then had been kept secret by patrician magistrates and priests. Their work produced the Twelve Tables, but their autocratic behaviour provoked the plebs to withdraw again to the Mons Sacer, this time explicitly invoking the protection of the supreme god. The secession ended with the decemviri's resignation and an amnesty supervised by the pontifex maximus Quintus Furius. When the plebs returned, they dedicated the hill of their retreat to Jupiter as a symbol and guarantor of the unity of the Roman res publica. The plebeians eventually gained access to nearly all offices and most priesthoods. The one post that remained closed to them was the Flamen Dialis.

  • King Numa Pompilius, the second king of Rome, needed to know how to avert lightning. Ancient tradition held that he managed to trap the woodland gods Picus and Faunus by making them drunk, then forced them to summon Jupiter down to earth at the Aventine Hill, which gave the god the epithet Iuppiter Elicius. When Jupiter arrived and demanded human sacrifices in exchange for the knowledge Numa sought, the king deflected each request with a substitution: an onion bulb in place of a head, hairs in place of men's lives, a fish instead of a soul. Jupiter, outmanoeuvred by the pious king's wordplay, accepted. The following morning, after throwing three lightning bolts across a clear sky, he sent down a shield from heaven. Because the shield had no angles, Numa named it ancile; recognizing that it contained the fate of the Roman imperium, he commissioned the smith Mamurius Veturius to make many copies, disguising the original among the replicas. Mamurius asked for only one reward: that his name be sung in the last of the Salii's ritual songs. Tullus Hostilius, the third king, fared differently. Warlike and contemptuous of religion, he conquered the Albans through the duel of the Horatii and Curiatii and destroyed Alba Longa. Omens in the form of a rain of stones fell on the Alban Mount because the displaced Albans had abandoned their ancestral rites at Jupiter's sanctuary there. A voice from the grove demanded the rites be resumed. A plague followed. Tullus, now ill himself, abandoned his warlike confidence and began to dabble in petty superstitions. He found a book of Numa's containing a secret rite for evoking Iuppiter Elicius and attempted to perform it, but executed it incorrectly. Jupiter threw a lightning bolt that burned down the king's house and killed him. Tarquin the Elder's encounter with Jupiter came in a different register: as a portent rather than a punishment. An eagle swooped down as Tarquin approached Rome, removed his hat, flew screaming in circles, replaced the hat on his head, and flew away. His wife Tanaquil read the sign by the bird's species, the quadrant of the sky from which it had descended, the god who sent it, and its contact with the head, the noblest part of a man, and interpreted it as a promise of kingship.

  • The Ides, the midpoint of each month and the night of the full moon, was sacred to Jupiter because on that day heavenly light shone both day and night. Some or all Ides were designated Feriae Iovis. On those days, a white lamb called the ovis idulis was led along Rome's Sacred Way to the Capitoline Citadel and sacrificed. The foundation rites of Jupiter's temples as Optimus Maximus, Victor, and Invictus fell on the Ides, as did his two Epula Iovis festivals. The nundinae, recurring every ninth day, gave rural people the chance to come into the city to sell goods and to learn of religious and political edicts, which were posted publicly for three days. According to tradition, King Servius Tullius instituted these market-day festivals. During the Republican era, more fixed holidays on the Roman calendar were devoted to Jupiter than to any other deity. Three festivals tied to viniculture fell under his patronage, since grapes were exceptionally vulnerable to bad weather. The rustic Vinalia altera on the 19th of August asked for fair weather to ripen the harvest. When the grapes were ready, a sheep was sacrificed and the Flamen Dialis cut the first grape of the season. The Meditrinalia on the 11th of October marked the end of the harvest; new wine was pressed and then mixed with old wine to control fermentation. At the Vinalia urbana on the 23rd of April, new wine was poured in large quantities into a ditch near the temple of Venus Erycina on the Capitol as an offering to Jupiter. The two Epula Iovis festivals, feasts of Jove held on the 13th of September and the 13th of November, were accompanied by flutes. By the 3rd century BC they had taken on the character of a lectisternium, a public banquet at which a deity's image was placed on a couch so the god could be understood to recline at the meal alongside the worshippers. The Ludi Romani of September and the Ludi Plebei of November followed the Epula Iovis by one day each, the games of September held in the Circus Maximus after a procession from the Capitol, the Ludi Plebei probably established in 534 BC in the Circus Flaminius.

  • Georg Wissowa, the 19th-century philologist, argued that Jupiter is unique among Indo-European religions: he is the only case in which the original sky god preserved his name, his identity, and his core prerogatives without being displaced or substantially reshaped. His Latin name Iuppiter derived from the Old Latin vocative compound of Iou and pater, which replaced the older nominative Ious. Deeper back, scholars trace this to the Proto-Italic Djous Pater and ultimately to the Proto-Indo-European vocative compound meaning "O Father Sky-god." The same root produced Zeus in Greek, Dyaus Pita in Vedic Sanskrit, and Ziu in the old Germanic languages. Jupiter's epithets are a catalogue of his qualities and functions. Optimus Maximus, the best and greatest, was Cicero's formulation: optumus for the benefits he bestowed, maximus for his strength. Lucetius referred not to daylight, as some ancient scholars thought, but to lightning, as the carmen Saliare makes clear. Elicius described him as the one who opens the reservoirs of rain. Stator, from stare, "to stand," named him as the one who makes soldiers hold firm. Feretrius, housed in what was said to be the first temple ever built in Rome, erected by Romulus, was connected with the spoils of war and with solemn oaths sworn over the sacred flint stone kept in the shrine. Victor and Invictus denoted his power of conquest. Jupiter Dolichenus, from Doliche in Syria, blended the Roman god with a Baal deity of weather and war, and became especially popular among soldiers stationed along the Danube at Carnuntum from the time of Vespasian. Jupiter Poeninus was worshipped in a sanctuary near the Great St Bernard Pass. When Hadrian built Aelia Capitolina on the site of Jerusalem, a temple to Jupiter Capitolinus replaced the destroyed Temple. The god's linguistic footprints run through every major European language. The Roman custom of swearing by Jove gave English the expression "by Jove." The adjective jovial comes from the belief that those born under Jupiter's planet were jolly and optimistic. The Latin Iovis Dies, Jupiter's day, became jeudi in French, jueves in Spanish, giovedi in Italian, and passed into Romanian, Catalan, Galician, Friulian, and Provencal under closely related forms. Thursday in English carries the same idea through the Germanic equivalent, the day of the sky god Ziu. The planet named after Jupiter carries the god's association with sovereignty into astronomy, and the noun jovial carries his temperament into everyday speech, more than two thousand years after the last Roman consul swore an oath in his name.

Common questions

Who was Jupiter in Roman religion?

Jupiter was the chief deity of Roman state religion and king of the gods throughout the Republican and Imperial eras. He was the god of the sky and thunder, the divine witness to oaths, and the guarantor of justice and good government. His primary symbols were the thunderbolt and the eagle.

What was the Temple of Jupiter Optimus Maximus and where was it located?

The Temple of Jupiter Optimus Maximus stood on the Capitoline Hill in Rome. It was begun by Tarquinius Priscus, completed by Tarquinius Superbus, and inaugurated on the 13th of September 509 BC. It served as the architectural model for Jupiter's provincial temples across the Roman Empire.

What were the duties and restrictions of the Flamen Dialis, Jupiter's high priest?

The Flamen Dialis was the highest-ranking of the fifteen flamines in Rome's official cult. He could not ride a horse, swear an oath, see the army outside the pomerium, or touch anything connected with death. He was required to keep his pointed hat and clothing on whenever he was outdoors, and he held a seat in the Roman Senate.

What is the origin of the word jovial and how does it relate to Jupiter?

Jovial originally described people born under the planet Jupiter, who were believed to be jolly, optimistic, and buoyant in temperament. The word derives directly from Jove, the alternate Latin name for Jupiter.

What role did Jupiter play in the Roman Conflict of the Orders?

Both patricians and plebeians claimed Jupiter's favour during the class struggle known as the Conflict of the Orders. During the first secessio, the plebs withdrew to the Mons Sacer three Roman miles northeast of Rome and consecrated its summit to Jupiter Territor. Fear of Jupiter's wrath was cited as a factor in resolving both the first and second secessions.

What days of the week are named after Jupiter in European languages?

The Roman name Iovis Dies, meaning Jupiter's day, gave rise to jeudi in French, jueves in Spanish, giovedi in Italian, joi in Romanian, and cognate forms in Catalan, Galician, Friulian, and Provencal. The English name Thursday traces the same concept through the Germanic sky god Ziu.

All sources

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