Janus

In ancient Roman religion and mythology, Janus (Latin: Ianus) 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 month of January was named in honor of Janus by the Romans.

Read more about Janus:  Etymology, Theology and Functions, Temples, Cult Epithets, Rites, Myths, Origin, Legends and History, Janus in Etruria, Association With Non-Roman Gods, Legacy, Cats, Literature