Janus, the ancient Roman god of beginnings and transitions, gave January its name and is linked with New Year changes.
Romans associated Janus with doorways, gates, passages, and movement from one state to another. He was commonly depicted with two faces, one looking forward and one looking backward, making him a natural symbol for reflecting on the past while anticipating the future.
The Roman month Januarius, named for Janus, eventually supplied the English name January. January became the first month of the Roman calendar after calendar reforms traditionally associated with the second century BCE.
Janus should not be confused with Saturn, whose festival Saturnalia was also important in ancient Rome but was not the source of January’s name. Modern New Year customs are diverse, while the connection between Janus and January comes from Roman religion and calendar history.