In ancient Roman religion and mythology, Janus is the god of beginnings and transitions, thence also of gates, doors, doorways, endings and time. He is usually a two-faced god since he looks to the future and the past. The Romans dedicated the month of January to Janus. His most apparent remnant in modern culture is his namesake, the month of January.
Though he was usually depicted with two faces looking in opposite directions (Janus Geminus (twin Janus) or Bifrons), in some places he was Janus Quadrifrons (the four-faced). The Romans associated Janus with the Etruscan deity Ani.
Janus was frequently used to symbolize change and transitions such as the progression of past to future, of one condition to another, of one vision to another, and of one universe to another. Hence, Janus was worshipped at the beginnings of the harvest and planting times, as well as marriages, births and other beginnings. He was representative of the middle ground between barbarity and civilization, rural country and urban cities, and youth and adulthood.