Latin: Januarius. Named after the god Janus.
Janus - From Roman god of gates, doorways, beginnings, and endings.
January was added to the calendar in the 8th century B.C. by the Roman King Numa Pompilius, who established the basic Roman calendar. Previously, the calendar had only ten months, March through December. December roughly translates from Latin as "tenth." The winter months were not counted as the calendar was mostly used for planting cycles. Numa considered the year to have 355 days. Two extra months were added at the end, with February being the shortest month. Several leap days were added to adjust for planting cycles. Later on, Julius Caesar added ten more days making the calendar have 365 days for most years; much closer, but still not exact. It would take more than 1500 years before a much better refinement was made.
January • February • March • April • May • June • July • August • September • October • November • December
January • February • March • April • May • June • July • August • September • October • November • December