(European mythology)
An old Italian deity, represented with two faces, looking different ways. His double-gated temple on the Forum in Rome had a symbolic significance: it was open in time of war and closed in time of peace. Janus may have been connected with the fortunes of war because any army had to pass through a gateway in order to start a campaign. An ianua, ‘entrance gate’, has two sides and presumably represents the two possible outcomes of any future event—success or failure.
From this military association Janus developed into a god of all ‘beginnings’. The month of January was sacred to him—today Europeans continue to look forwards and backwards at this time—while as Janus Quadrifrons, ‘four heads’, he presided over the four seasons. The Romans named Janus first in any list of gods invoked in prayer.