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The temple of Janus in Rome was situated in a street named Argiletum, an important road that connected the Roman Forum and the residential areas in the northeast. It was a small, wooden temple, and the building material suggests that the cult of Janus was of a venerable old age. This is confirmed by several facts. The oldest lists of gods usually began with his name; he was surnamed divom deus, a very ancient form of Latin meaning "the god's god"; and his portrait can be found on the oldest Roman coins. Janus was, therefore, a very old and important Roman god. Before every sacrifice, he was invoked and received a libation.
The temple in the Argiletum consisted of two gates; the cult statue was between them. It was a very ancient statue; the author Pliny the Elder mentions it as proof that the sculptor's art existed in Italy in the earliest times (Natural history 36.58). The god was portrayed with two bearded heads. The fingers of his hands were placed in strange positions, which Pliny interpreted as an indication of the number 355, which he thought was a reference to the number of days of the oldest Roman calendar. This may be true, but it is, of course, pure speculation.
Janus also has a temple at Rome with double doors, which they call the gates of war; for the temple always stands open in time of war, but is closed when peace has come. The latter was a difficult matter, and it rarely happened, since the realm was always engaged in some war, as its increasing size brought it into collision with the barbarous nations which encompassed it round about. But in the time of Augustus it was closed, after he had overthrown Marc Antony; and before that, when Marcus Atilius and Titus Manlius were consuls, it was closed a short time; then war broke out again at once, and it was opened.Plutarch goes on to say that during the reign of the legendary king Numa, the gates were always closed, and that Numa had invented the rule that they were to remain open in wartime. But this can not be true. In the fifth and fourth centuries, there were several warless years, but the gates were not closed; and we simply do not know why Manlius closed the gate in 235 BCE. The legend about Numa is not found in our sources until a century later (Calpurnius Piso, fragment 9).[Plutarch, Life of king Numa 20.1-2
tr.Bernadotte Perrin]
It was the will of our ancestors that the gateway of Janus Quirinus should be shut when victories had secured peace by land and sea throughout the whole empire of the Roman people; from the foundation of the city to my birth, tradition records that it was shut only twice [by Numa and Manlius], but while I was the leading citizen the Senate resolved that it should be shut on three occasions.The gate was locked for the first time in January 29, after Augustus had defeated Marc Antony and Cleopatra, and again in the autumn of 25, when the Spanish Cantabrians were subdued. The Christian author Orosius states that the gates of Janus were closed for the third time in 1 BCE, and remained closed for no less than twelve years (History of the world against the pagans 6.22). This tells more about Orosius' theological than historical interests: during the twelve years of Christ's childhood, the Romans were involved in several wars (e.g., in Germania, where they suffered a famous defeat in the Teutoburg Forest). The truth is that we do not known when the gates were closed for the third time.[Augustus, My achievements 13;
tr. P. Brunt and J. Moore]
The poet Virgil helped the emperor invent the tradition. In the Aeneid, the national epic of the Romans, the simple fact that every consul left the Roman Forum through the Argiletum (Rome's most important road) is blown up to an ancient ritual:
There was a sacred custom in Latium, Land of the West, which the Alban Cities continuously observed, and Rome, supreme in all the world, observes today when Romans first stir Mars to engage battle, alike if they prepare to launch war's miseries with might and main on Getae, Hyrcanians, or Arabs, or to journey to India, in the track of dawn, and to bid the Parthians hand our standards back. There are twin Gates of War, for by that name men call them; and they are hallowed by men's awe and the dread presence of heartless Mars. A hundred bars of bronze, and iron's tough, everlasting strength, close them, and Janus, never moving from that threshold, is their guard. When the senators have irrevocably decided for battle, the consul himself, a figure conspicuous in Quirine toga of State and Gabine cincture, unbolts these gates, and their hinge-posts groan; it is he who calls the fighting forth, then the rest of their manhood follows, and the bronze horns, in hoarse assent, add their breath.In another passage, Virgil explains the meaning of the ritual closing of the gates:[Virgil, Aeneid, 7.601-615
tr. W.F. Jackson Knight]
The terrible iron-constricted Gates of War shall shut; and safe within them shall stay the godless and ghastly Lust of Blood, propped on his pitiless piled armory, and still roaring from gory mouth, but held fast by a hundred chains of bronze knotted behind his back.[Virgil, Aeneid, 1.293-296]
In spite -or rather: because- of this ambiguity, the closing of the Gates of War was a powerful symbol. Later emperors used it as well. After Nero's general Corbulo had defeated the Parthians, the ruler shut the doors in 66. Coins with the legend PACE Popvlis Romanis VBIQve PARTA IANVM CLVSIT ("He closed the gate of Janus when the Roman people everywhere enjoyed peace") were struck to commemorate this occasion. In 75, it was Vespasian's turn.
In the meantime, the cult had changed. The emperor Domitian had changed the old cult statue and replaced it with a bust with four heads, which oversaw four forums: the Forum of Peace, the Forum Transitorium, the Forum of Julius Caesar, and the Roman Forum. This is told by the poet Martial (Epigram 10.28.5-6), and his words enable us to establish the place of the temple in the immediate neighborhood of the Senate building (Curia Julia). Excavations in 1997-2000 did not result in a more precise identification of the foundation of the wooden shrine (instead, a monumental farm from the age of Charlemagne was discovered).
