THE CALENDAR WAS CREATED BY ITALIANS

By Matthew V. Grieco

Beware the Ides of March. As everyone recalls, Julius Caesar was murdered on March 15, 44 B.C.

But what exactly was the “Ides”? The Roman calendar was configured differently from our own. Rather than designating each day of the month a number from 1 to 31, the Roman month had three fixed points: the Kalends (the 1st of the month), the Ides (the 15th of March, May, July, and October, and the 13th of the remaining months; the mnemonic device MaMaJuliO will serve), and the Nones (the 9th day, counting inclusively, before the Ides, and thus the 7th of MaMaJuliO and the 5th of the remaining months). The Romans counted backwards from those fixed points. So, March 14th was “the day before the Ides of March.”

The original Roman calendar had 10 months, March through December. Vestiges of that calendar remain in the names of our months September, October, November, and December, which literally mean seventh, eighth, ninth, and tenth months. Quintilis (fifth month) was renamed July during the dictatorship of Julius Caesar, who was born in that month, and Sextilis (sixth month) was subsequently renamed August to honor the Emperor Augustus. In around 700 B.C., Numa Pompilius, the second king of Rome, reputedly added the months of January (for Janus, the two-faced god of portals) and February (in which was performed the Februa, a rite of expiation and purification). Just to round out the calendar, March was named for Mars, the god of war, April is derived from “aperire,” the Latin verb “to open” (the Earth opens in April), May was for Maia, the wife of the god Vulcan, and June was for Juno, the queen of the gods.

Even after the invention of January and February, the Roman lunar calendar only had 355 days. To bring that calendar into line with the seasons, an extra month, Mercedonius (for the god Mercury), of 22 or 23 days was intercalated in February. The system was clumsy and subject to political manipulation (an easy way to extend one’s term in office). It had fallen greatly out of whack with the solar calendar by 46-45 B.C., when Julius Caesar, with the assistance of some astronomers, reformed it to give us a calendar of 365 days, with an extra day added every 4 years (February 23rd was repeated).

Because the solar year is not exactly 365.25 days, but 365.242199 days, the Julian calendar slowly drifted out of solar alignment over the centuries. In 1582, the Italian Pope Gregory XIII slightly modified the calendar to reflect that century years not evenly divisible by 400 are not leap years. In addition, leap day was set at February 29th. And so, the calendar in use today is the product of Italian genius.