So the New Year is here, and I’m sure many of you will have made resolutions or goals for how you’re going to make this year better than the last. As humans in a modern world, we are ruled by time. Minutes, hours, days, weeks, months, and years dictate our lives – what we are legally allowed to do, how long we have to work, when our bills are due, when we can go on holiday. But even before we had precise modern ways to measure time, humans have marked the passing of time for thousands of years. When will the long days be coming again? When do I need to plant and harvest my crops? When will the harsh winter end?

Calendar for January, Book of Hours, use of St Omer, c 1318 – 1325. British Library.

The oldest known calendar comes from Scotland, dating to around 10,000 years ago. It is an arrangement of 12 pits and an arc found in Warren Field, Aberdeenshire, and is believed to have been used as a lunar calendar. In terms of a single object being used as a calendar, the claims are more contested. The Slatino Furnace model, a ceramic artefact found in Bulgaria, has been claimed by some to be the oldest known calendar representation, but this is not universally agreed. The Slatino Furnace model dates to c. 5000 BC and no one really knows what it is. On its largest flat side there is a clearly traced rough square grid with 30 cases, 12 of them marked with colour, which is what leads some to claim its use as a calendar. However, others have argued that it could be a vessel for grain with a connection to women and fertility.

Time keeping is known to have gone back to prehistoric periods that are at least as old as the Neolithic period (around 10,000 BC) but these tend to be structures like that at Warren Field which typically kept track of the solar years. Stonehenge in England, for example, precisely matches the direction of the midsummer sunrise and midwinter sunset. The oldest known calendar as we may recognise today dates to ancient Sumer, the earliest known civilisation of southern Mesopotamia, which was settled between c. 5500 and 4000 BC. The Sumerians divided a year into 12 lunar months of 29 or 30 days, with each month beginning with the sighting of a new moon. This gave a lunar year of 354 days, and so an extra month was added periodically to keep in line with the solar year of just over 365 days – similar to our use of a leap year today. However, the Sumerian calendar did not have weeks – Holy days and time off from work were usually celebrated on the first, seventh and fifteenth of each month, with feast days which varied from city to city added in between.

An aerial view of the site at Warren Field, Aberdeenshire. Aberdeenshire Council.

Whilst most early calendars were lunar, the Persians were among the first cultures to use a solar calendar. They used a 360 day calendar based on the sun with 12 months of 30 days, with a 13th month added every six years to keep the calendar synchronised. The solar calendar was probably introduced as the national calendar of the First Persian Empire in the reign of Artaxerxes I, c. 465 – 424 BC.

The Romans, however, had a year of 304 days divided into 10 months, with 8 day weeks. The year began in March, named after the God Mars who was regarded as an ancestor of the Roman people through his sons Romulus and Remus. March marked a return to the active life of farming, military campaigning, and sailing and was densely packed with religious observances. Julius Caesar made huge changes to the year, replacing it with a solar calendar which began on January 1st and ended on December 31st and was divided by 12 months. It was introduced in 46 BC, becoming known as the Julian calendar which remained in almost universal use in Europe until 1582.

An Ancient Egyptian calendar from the Temple of Karnak near Luxor, Egypt. ENCYCLOPÆDIA BRITANNICA.

In medieval Europe, years were often referred to by regnal years (how many years the monarch had been on the throne). The Anno Domini system still used today, meaning “in the year of our Lord”, was created in the 6th century by a Christian monk, Dionysius Exiguus, but it didn’t gain widespread use in Europe until the 11th century, with Portugal being the last Western European country to adopt the system in 1422. There were rival Christian calendars to the Anno Domini system – the complication of AD was that with Christ’s birth being the starting point, you had to calculate time going forwards or backwards from that point. Many instead opted to use the Year of Creation (fixed by the Eastern Orthodox Church as 5509 BC and the Coptic Church 5500 BC) as their starting point, meaning one only had to count forwards.

The Islamic calendar was based on a sermon by Muhammad held on 9 Dhu al-Hijjah AH 10, or 6th March 632 AD in the Julian calendar. Here, Muhammad named four ‘forbidden months’ where battles were forbidden. This calendar was still based on a 12 month year, however.

An image of Muhammad’s sermon from a 17th century Ottoman copy of an early 14th century manuscript from Northwestern Iran or northern Iraq.

The ancient calendars of the Maya were the most complex of all the ancient calendars. The Maya had 2 different years which ran simultaneously: the 260-day Sacred Round, or tzolkin, and the 365-day Vague Year, or haab. The Sacred Round was used to determine important activities related to the gods and humans such as naming individuals, predicting the future, deciding auspicious dates for battles, marriages, and so on. The Sacred Round had 2 cycles within it – the numbers 1 – 13 that would be coupled with 20 different day names. Both the cycles of numbers and names were repeated, bringing different combinations each ‘month’. The Vague Year, meanwhile, had a similar number of days to our modern year and consisted of 18 months with 20 days, and an unlucky 5-day period at the end of the year. This calendar was based on the solar year, and governed the seasons and agriculture.

The Sacred Round and Vague Year calendars worked in conjunction with each other to make the Calendar Round, represented by two wheels rotating in different directions. The Calendar round cycle took approximately 52 years to complete. There was also the Long Count which was used to calculate longer periods of time, with each cycle calculated to be 2,880,000 days (about 7885 solar years). The Mayans believed that the universe is destroyed and then recreated at the start of each universal cycle. This is what led to the prophecies in 2012 of the end of the world – the Mayan calendar was completing its current cycle of the Long Count which converted to 11:11 Universal Time (UTC), December 21, 2012.

The Aztec sun stone held at the National Anthropology Museum in Mexico City carved between 1502 and 1521. Whilst not a functioning calendar, it uses the calendrical glyphs. Right, a picture of the stone from 1917 showing its scale.

Today, the most widely used civil calendar in the world is the Gregorian calendar. Whilst the Julian calendar solved many problems, in 1582 reforms were introduced by Pope Gregory XIII to compensate for the fact that the system used by the Julian calendar added about three days every four centuries, making time slightly off. The Gregorian calendar has the same months and month lengths as the Julian calendar, but introduced leap years every four years which add an extra day. Years evenly divisible by 100 are not leap years, whilst years evenly divisible by 400 remain leap years.

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In the 50 years after Pope Gregory introduced the new calendar, most European countries adopted the new calendar. England and its dominions decided not to follow the new calendar, but this was complicated and meant that people often had to write documents using two dates, one with the new Gregorian calendar and one with the old Julian. England remained on the Julian calendar until 1750, when the government decided to bring the country and all of its territories in line with most of the rest of Europe. The 2nd September, 1752, was chosen as the date to change, meaning that when people went to bed that night, they woke up on 14th September. A few other European countries remained on the Julian calendar for long after, however – Russia didn’t adopt the Gregorian calendar until 1918, and Greece changed in 1923.

A copy of a calendar page for the French Republic month of Nivôse (21 December – 19 January), 1797 – 1798.

Today, it is unlikely that our calendar will change much in future. Whilst we consider calendars to be fairly free from politics, as with most things, even time can be politicised. One famous example is the French Republican Calendar, introduced during the French Revolution. Between late 1793 to 1805, the French government used this revolutionary calendar designed in part to remove all religious and royalist influences from the calendar, and was part of a larger attempt at decimalisation in France. Years were dated from the first year of the republic, with the beginning of each year set at midnight, beginning on the day the apparent autumnal equinox falls at the Paris Observatory. There were still 12 months, but they were divided into three 10-day weeks, whilst a day was divided into 10 hours, each hour 100 minutes, and each minute 100 seconds. The calendar was abolished in 1805 by Napoleon due to the difficulties of using the new calendar and its unpopularity amongst citizens.

So, as you begin a new year and consider making (and trying to stick to) goals and resolutions, and go back to the monotony of school and work, just remember that you are part of a very long time keeping history!

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