A history of the Calendar

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Our calendar has many roots and predecessors, but all have contributed in some way to our current Gregorian Calendar. Current, because as with all pieces of imagination (and time is one of the largest inventions of Man) we are constantly reviewing and playing with it. For example, by the end of the year 2000, not only had we experienced the not unexpected leap year, but we had also experienced a less common leap second. We have mastered our invention of the calendar and our perception of time so well that we are now able to fine tune them by adding seconds when necessary to keep time on Earth perfectly aligned with the rest of the Universe. It is with this connection with Stellar bodies that we can discover the origins of Man's Calendar.

What came first: 360º in a circle or the discovery that the Earth took approximately 360 days to revolve around the Earth?

Ancient civilizations and the Lunar Calendar:

Nearly every ancient culture worshipped a moon god. The Ancient Egyptians called their moon god Khonsu, the Sumarians Nanna. The Greek and Roman goddess of the moon had three faces: she was Selene (Luna) when full, Artemis (Diana) when waxing (waxing means that the moon is getting fuller, the opposite when the crescent is shrinking is waning) and Hecate when in her dark form. This worshiping of the Moon (which caries on today) gave rise to the lunar calendar. The Lunar calendar gave many civilizations across the globe from the Sumer and Chinese to the Anasazi in Arizona, to the ancient Greeks a year which was based on a 12 month lunar cycle, with each month equal to approximately 29.5 days in length. This gave rise to a 354 day year. Unfortunately, this early dependence on the Moon as a corner stone in the concept of the year gave rise to a highly inaccurate calendar useless for planning the planting of seeds and harvesting of crops, for as we can see, after 1 solar year (our calendar) the lunar calendar is running 11 days fast, after 2 years 22 years and it is obviously not long before Summer is when Winter is, Autumn when Spring should be and vice-versa.

The Months

The months in our calendar were first named by the mythic first king of Rome, Romulus, when he founded the city in 753B.C. which was year 1 in the Roman Calendar and was known as ab urbe condita (AUC), 'from the founding of the city". The calendar was initially set up with 10 months for a year that totaled 304 days. Why 10 months; we can only surmise that it was a continuation of the Romans infatuation with the number 10, which appeared throughout the way the Empire counted. Romulus named the first four months: Martis (the god of War), Aprilis, Maius (a local Italian goddess) and Junius (the queen of Latin gods). After this he simply named them:Quintilis (Latin for fifth), Sextilis (sixth), September (seventh), October (eighth), November (ninth) and December (tenth). Around 700BC Romulus' successor King Numa added two more months (Januarius and Februarius) to the calendar to try and satisfy farmers who demanded a better system for keeping track of the seasons. This gave rise to a year equal in length to the lunar year, to which he added one more day for superstitious reasons to get a year of 355 days. The farmers realised that this new calendar was also flawed and over the next few years the Romans introduced a variety of different correction methods, such as introducing an extra month every 4 or 8 years to fix it.

It was not until Caesar returned to Rome from the wars he had been fighting in Egypt in 46BC that a major reform of the calendar took place. Caesar's Philosophers and Mathematicians introduced a year which was 365 and a quarter days long, which like ourselves they took care of by having three consecutive years of 365 days and one of 366 days. After years of neglect, to bring the Roman calendar back into line with the vernal equinox which traditionally occurs on the 25th March, Caesar ordered two extra months to be added to 46BC, consisting of 33 and 34 days inserted between November and December. This year Caeser named the ultimus annus confusionis (the last year of confusion). To complete his calendar reforms the first day of the new year was moved from March to January, nearer to the Winter solstice. To create a standard year of 365 days, he inserted 10 days into the months to create 12 alternating 30 and 31 day months with the exception of February which had 29 days or 30 days in a leap year. Thus, by the end of 46BC, the Romans had had a year which consisted of 445 days and had gained the most accurate calendar ever invented. The Senate later renamed Quintilius to Julius in his honour. The Senate also renamed Sextilis as Augustus after the Emporer, who corrected a minor flaw created by leap years being celebrated at the wrong time. So that this honour was not less than Ceaser's, they changed the length of the 8th month to 31 days from 30 days. This extra day was stolen from February. To avoid three 31 day months in a row, the lengths of September, October, November and December were switched.

The days

Emporer Constantine in 321 reformed Ceaser calendar by introducing a religious element to it. A holy day was introduced, Christian holidays such as Christmas day were given fixed dates and the timing of Easter celebrations were taken into consideration. On dies Solis, the Sun's day, everybody was ordered not to work. The choice of this day as the Sabbath was not without controversy. The final change he made was to change the week from 8 days in length to 7 days. This is probably due to the Astrological significance of the seven known planets at the time. Indeed the days were named with the planets names, who in turn were named with the names of gods.

When is Easter?

This question was posed by Constantine in 325 to a gathering of Christian leaders at a gathering in the Turkish village of Nicaea (modern day Iznik). After a summer of debate, this question was unresolved due to many factors. Use the Easter calculator to calculate the date when Easter was or when it will be in a particular year.

Jamie Coventry
10th January 2001