Temple of Janus (Roman Forum)

In ancient Rome, the main Temple of Janus stood in the Roman Forum near the Argiletum. It had doors on both ends, and inside was a statue of Janus, the two-faced god of boundaries. The Temple doors (the "Gates of Janus") were closed in times of peace and opened in times of war.

According to Livy 1.19 the second king of Rome, Numa Pompilius, decided to distract the early, warlike Romans from their violent ways by instilling in them awe and reverence. His projects included promoting religion, certain priesthoods, and the building of temples as a distraction with the beneficial effect of imbuing spirituality. The Temple of Janus was Numa's most famous temple project.

Plutarch, in Life of King Numa, wrote:

[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 Mark 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.

During Numa's reign, the Gates of the Temple of Janus were closed and Rome remained at peace. The next king, Tullus Hostilius, opened the Gates of Janus when he went to war with Alba Longa. The Gates of Janus remained open for the next 400 years until after the First Punic War when T. Manlius Torquatus closed the Gates of Janus in 235 BC. This closure lasted about eight years. War with the Gauls in Northern Italy forced the Gates of Janus to reopen. They did not close again until 29 BC, following the deaths of Antony and Cleopatra.

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