Why Just 28 days in February?

February didn’t use to be in the calendar at all, neither did January. The early calendars were only ten months long (304 days), beginning with March as the first month. As far as the ancients were concerned, winter was lost time. Nothing happened in the cold months. The calendar was an agricultural and lunar cycle concern. Apart from knowing when to plant, why did one need to count the days?

January and February were added to make the twelve months. Every other year, February was shortened and a leap month (Intercalaris) was added in an attempt to realign lunar cycles with the solar calendar. The lengths of the years in a four year cycle of this lunisolar calendar were 355, 377, 355, and 378 days. This added up to 4 days too many to stay in sync with the solar year.

Eventually Julius Caesar asked an astronomer, Sosigenes of Alexandria, Egypt, to devise a better calendar. He abandoned aligning the months with lunar cycles, and adopted months of 30 or 31 days length, keeping February at 28 days. He introduced an extra day in February in leap years. The calendar year was realigned to begin with January.  What resulted is called the Julian Calendar.

Julius Caesar re-named the 5th month (when March was the first month) after himself. His successor, Augustus Caesar, re-named the 6th month after himself.

The first day of each month was called Kalendae, or calends. Debts were due on this day, so books to track payments were called calendarium (account book) from which we get our modern day calendar. The name of the month comes from the Latin Februarius “of Februa.” Februa was a Roman festival of purification held on February fifteenth.

Remember, February was the last month of the year when it was created. It needed only enough even days to fill out the 365 day calendar.


The origin of the names for the other months of the year is as follows:

January: Latin Januarius mensis "month of Janus"

Janus is the Roman god of gates and doorways, depicted with two faces looking in opposite directions. His festival month is January. Januarius had 29 days, until Julius Caesar when it became 31 days long.

March: Latin Martius "of Mars." March was the original beginning of the year, and the time for the resumption of war. Mars is the Roman god of war.

April: Latin Aprilis  Greek Aphro, short for Aphrodite, goddess of love and beauty. She is identified with the Roman goddess Venus.

May: Latin Maius "of Maia."  Maia (meaning "the great one") is the Italic goddess of spring, the daughter of Faunus, and wife of Vulcan.

June:  Latin Junius "of Juno."  Juno is the principle goddess of the Roman Pantheon. She is the goddess of marriage and the well-being of women. She is the wife and sister of Jupiter.

July: Latin Julius "Julius." Julius Caesar reformed the Roman calendar (hence the Julian calendar) in 46 BC. In the process, he renamed this month after himself.

August:  Latin Augustus "Augustus."  Augustus Caesar clarified and completed the calendar reform of Julius Caesar. In the process, he also renamed this month after himself.

September, October, November and December are the numbered months for the Latin: septem, “seven”; octo, “eight”; novem, “nine” and decem, “ten.” We know that September is the ninth month in our calendar etc., but remember the months were named during the time when the first month was March.