The month of January, named for the two-headed Roman god Janus, originally appeared towards the end of the calendar year, along with the equally dark and boing February, the last month of the year.

Then power brokers in Rome decided it would be more politically advantageous to inaugurate their new consuls in January, two months before the country typically went off to wage war in March, named for the Mars, the god of war.  The rest is history.

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