Happy January, named for the Roman god "Janus." Janus represented beginnings & endings, ins & outs at the same time. Thus, he is usually pictured with two faces. One of these dichotomies represented is the beginning and the and ending of the year. Hence, January being "his" month.
He also represented the beginning and ending of war, though Mars was the god of war, with Minerva playing some role in this. He was the god of "entryways", such as gates, doorways and arches.
 |
In a broader sense, he was the god of transitions. As such, he was seen as the representation of the prime beginning and end of the universe itself.
Romans turned concepts into deities much more frequently than Greeks did. Thus, there was no Greek equivalent of Janus.
For more reading on Janus:
Dualities from/based on Ecclesiastes
