The tradition of making New Year’s resolutions goes all the way back to ancient Rome. In 46 B.C., Julius Caesar developed a new calendar and named the first month of the year after Janus, the god of beginnings and endings.
Janus has always been depicted with two faces, one on the back of his head that allowed him to look into the past and one on the front of his head that allowed him to look into the future. At midnight on December 31st, the Romans imagined him looking back at the old year and looking forward to the new year. Therefore, he became the symbol of the resolutions made on the first day of each year when Romans asked their enemies for forgiveness.