Calendars

The New Year was celebrated a few weeks ago, and as usual I stayed up until midnight to be present for the animals. Some of the fireworks were particularly loud this year. Increasingly, at the turn of each year I really feel that it would be better celebrated a little later. With the advent of spring, perhaps. A time when we feel less like hibernating, and more like emerging to greet the outside world. The season of growth and renewal. Of nesting and nurturing. Of longer hours of daylight and – if we’re lucky – a bit more sunshine.

I began researching why we mark new year on the 1st of January. The answer lies in a time before the common era (BCE), when the ten-month Roman calendar of 304 days was in place. At that time, the calendar started with the month of March. In 713 BCE, Roman King Numa Pompilious added January, followed by February, to the end of the calendar. The resulting Roman Republican Calendar comprised twelve months and was based on the lunar calendar of 354 days in a year.

Chaotic Calendar

To align the months with the solar cycle, an extra month of 27 or 28 days – Mercedonius – was added to the calendar every two or three years. However, this process was often abused by politicians – who’d have guessed? Those in charge of deciding if and when to add extra days to the year were people in power. By adding or skipping days, politicians could extend their time in office. Or reduce the time their opponents were in office. They could also declare extra days in a year were holidays, meaning votes on new laws were postponed. And as the first day of a month was the time to pay debts, changes to the calendar could also disrupt financial obligations. The result was a chaotic timeline based on the lunar cycle which was occasionally in synch with the solar pattern.

Enter Julias Caesar who, in 46 BCE, decided to end political manipulation of the calendar. By adding Mercedonius, and another two extra months to that one year, he created what became known as ‘The Year of Confusion’ of 445 days. In doing so, Caesar synchronised the lunar calendar to the solar cycle.

Julian Calendar

After the extraordinarily long year, from 45 BCE Caesar’s Julian Calendar replaced the Roman Republican Calendar. Caesar called upon the expertise of astronomer Sosigenes of Alexandria to calculate the time taken by Earth to orbit the Sun. The measurement came out at 365¼ days. The resultant calendar had 365 days in a year with an extra day added every 4 years to make a leap year. The occasional month of Mercedonius was no longer needed.

Caesar also determined that the two months which Pompilious had added to the end of the year, January and February, should be brought to the beginning of the year. January was named after Janus, the Roman two-faced god of doorways, beginnings, and transitions. It was thought to be a fitting name with which to begin the year, and the first of January replaced 1 March as the start of the calendar year.

After the fall of the Roman Empire, in place of 1 January, 25 March was adopted gradually across parts of Europe as the start of the new year. England made the change in 1155. More on this below.

Reset

The calculation of Earth’s time to orbit the Sun was slightly out. Earth actually takes about 11 minutes and 14 seconds less than 365¼ days to orbit the Sun. So at the time of a leap year, the deficit is around 45 minutes. In other words, adding a leap year day every 4 years leaves us about 45 minutes in arrears. Which adds up to about one day every 128 years. The Romans double counted their groups of four years, further confusing the timeline. Rather than 1, 2, 3, 4 (leap year), 5, 6, 7, 8 (leap year), the Romans counted one, two, three, four (leap year); four, five, six, seven (leap year). Over the centuries, this becomes a not insignificant amount of time.

To correct the drift and address the lost days – which by now numbered 10 – Pope Gregory XIII introduced the Gregorian calendar in 1582 CE. The main reason to bring in a new calendar system was religion. Easter was pulling further away from spring every year and by 1582 it fell on 11 March, the end of winter. The Church wanted to bring the date for Easter more in line with the astronomical beginning of spring on 21 March. Easter is traditionally the Sunday which falls after the first full moon on/after 21 March (the Paschal Full Moon).

Missing Days

Owing to the ten days of drift, it was decided that 10 days would be removed from the calendar in 1582. October was the month selected, to avoid missing any significant Christian festivals. For the countries which adopted the new calendar, 4 October was followed immediately by 15 October.

The Gregorian calendar was taken up by Italy, Spain, Poland, Portugal, France, parts of the Netherlands, and some regions of Germany. At this time, England was under the Protestant rule of Queen Elizabeth I. Ongoing tensions between the Protestant and Catholic churches meant that the Gregorian calendar was not adopted at this point, resulting in countries being out of synch for a number of years.

This ten day difference is particularly noticeable in records of notable dates. The Spanish Armada, for example, was sighted off the coast of England on 19 July 1588 according to English records. Meanwhile the Spanish fleet noted their first sighting of England was on 29 July 1588.

Late Adopters

It was over the next three centuries that other countries adopted the calendar. Some referred to it as the ‘Improved Calendar‘, and others used it for civic purposes but not religious.

England was a late adopter and began using the Gregorian calendar in 1752. By this time an eleven day correction was needed to align dates with the new system. This date adjustment took place in September 1752 when the second of September was followed by the fourteenth of September. The month was chosen to minimise agricultural and financial disruption. Also because it avoided any significant religious dates.

A further adjustment was made so that the legal new year moved from 25 March to 1 January.

Tax Year

The tax year start date was also moved in 1752. Previously on 25 March, the tax year was moved to 5 April. This was to avoid paying tax on the eleven days which were lost that year. People protested that they were being asked to pay a full year’s tax, when eleven days of the year had been dropped.

A further calendar adjustment in 1800 moved the new tax year to 6 April.

New Year In March

All of which loops back to my original musing as to why new year is celebrated on 1 January. A time of year with fewer hours of daylight, unpredictable weather, when people might rather stay inside than go out. It seems Julias Caesar first selected January as the new year month, in celebration of the god Janus. After the fall of the Roman Empire, 25 March was adopted gradually across parts of Europe as the start of the new year. England made the change in 1155. The selection of this date has its roots in religion.

The twenty-fifth of March, Lady Day, is a date of high significance in the Christian calendar. According to Christian beliefs, this is the date on which the Angel Gabriel informed Virgin Mary that she would conceive Jesus Christ. Regardless of one’s own religious position, the 25 March feels a more natural time to celebrate new year. Emerging from the darker months of winter into the rebirth of spring seems a fitting time to celebrate.

When England adopted the Gregorian calendar in 1752, the date for New Year’s Day was also moved so the start of the legal year fell on 1 January. This brought England into line with the rest of Western Europe. The financial year remained tied to Lady Day, with the 11 day adjustment moving the date into April.

Personally, I still see the attraction of using winter as a time for semi-hibernation, and March as the first month of the new year.

 

Finally

To account for the extra quarter day taken for Earth to orbit the Sun, an extra day is added to February every four years. A leap year. But this overlooks the 11 minutes 14 seconds difference as mentioned in the reset paragraph. Adding a day every four years will eventually lead to a backward drift as was corrected with the introduction of the Gregorian Calendar.

To counter this, an extra calculation is applied to years which are multiples of 100. Leap years are usually identifiable as the years which are divisible by 4. If the year is a multiple of one hundred, to be a leap year it must be divisible by 400 (and therefore 4). This small correction allows – more or less – for the accumulation of time difference across the century.

Using this method, the year 1900 was not a leap year. Although divisible by 4, it is not divisible by 400. Two thousand, meanwhile, was a leap year as 400 goes into 2000 five times.

On which note, as it’s a cold and wet day in February, I will close this post and make a hot drink. I hope you enjoyed reading as much as I enjoyed researching.