The history of the calendar

The history of the calendar

Our ancestors used the sun, the moon and the stars to measure time and form the very first calendars (meaning register). The earth orbiting the sun marks the annual year. The moon cycle was the blueprint for the month and the weeks (28 days dived by the 4 quarter of the moon cycle – 7 day week).

The Ancient Greek word for moon ‘mene’ is the root for minute, month, and even menstruation. Very early on the correlation between the timescale of the moon cycle and the female fertility cycle was well understood.  Moon gods/goddesses were called upon for all kinds of fertility problems. These could be a lack of conceiving, problems with the menopause or failed harvests and food production.

The lunar month was the first properly understood time-measuring tool. It enabled hunter-gatherer societies during the Stone Age to forecast seasonal changes, schedule events/celebrations and stock up on food reserves for the winter months.

Animal bones found in the Dordogne region of France are believed to be the first moon calendars known to man. These archaeological finds date back to around 28,000 B.C. and show different patterns of notches that define the passing of time between the New Moon to the Full Moon. Find out more about the history of the lunar calendar. 

The Ancient Lunar year consisted of 12 moon cycles, determined by the four cornerstones of the year, the winter solstice (21st December = the shortest day of the year), the summer solstice (21st June = the longest day of the year) and the spring and autumn equinoxes (21st March and 23 September = when the length of the day equals night).

But since 12 moon cycles fall a few days short per year (354 days), a solution had to be found. So every other year a leap year with 13th moon cycle was introduced to bring the seasons back in sync with the Ancient Lunar year. The Ancient Greek, Roman and Chinese calendars all operated this system.

When Julius Ceasar arrived in 48 B.C. in Egypt, he did not only fall in love with Cleopatra, but he also immersed himself into Egyptian science. He was particularly intrigued by the way the Egyptian calendar system worked. At the time the Egyptian calendar was the only purely solar calendar of its time.  It counted 365 and 1/4 days per year. An astonishing achievement, considering it was first put in place around 4200 B.C.

Upon his return to Rome Caesar ordered a massive Roman calendar reform and the Julian calendar was born. The newly formed Roman year had only 12 months and the starting date (previously March, named after the War God Mars and the start date of the Roman marching season) was moved to the 1st January.  Ceasar named his birth month after himself, now July. His successor Augustus did the same and modestly name August after himself.

But for all the yearly time-keeping improvement that the Egyptian calendar brought, Cesar wisely kept all the lunar festivals and names of the previous months intact.  Otherwise, his reform would have been too radical and confusing. Can you imagine –  September (previously the seventh month) would theoretically now be the 9th and should really be called November and so on.

Had it not been for Ceasar’s enthusiasm for the Egyptian culture, he would have probably chosen the most efficient calendar system of its time. The Lunisolar Calendar as operated by the Sumerians and later Babylonians, which combined the solar and lunar cycle.

Caesar almost got it right, but there was a slight miscalculation in the Egyptian calendar when it came to leap years.  The solar year actually counts precisely 365 days, 5hours, 48minutes and 45 seconds. That difference would finally add up to 10 days!
In 1582 Pope Gregory XIII finally corrected this mishap and introduced another calendar reform which we still use to this day – the Gregorian Calendar.

But there was another error creeping in. The years (meaning the rotation of the earth around the sun) are slowing down – appropriately 1/2 a second per century. So in 1972, the answer was found by employing the ‘atomic clock’ and that is what all our computers, phones, alarm clocks use today for accurately measuring time. It is no longer connected to the stars, the moon and the heavens. We have disconnected ourselves from all these movements and now we follow the oscillations of atoms. This tool is called UTC – the Co-ordinated Universal Time. 

I am happy to follow the UTC clock to time my zoom calls and alarm clock. But when it comes to structuring my own life, I happily revert back to the Lunisolar calendar (the calendar model the LWTM lifestyle calendar is modeled on). This calendar does not only measure time,  but it also gives an insight into the ‘quality of time’, a fantastic tool to structure my life. 

To find out more about the LWTM lifestyle and holistic life goal planning please download our useful freebies package. 

 The history of the moon calendar

The Sumerian calendar

The Sumerian calendar

The Sumerians and later the Babylonians were the first known civilizations to use what we now recognize as a lunisolar calendar.

By the 21st century B.C. the Sumerians had come up with a solar year consisting of 360 days. It consisted of 12 lunar cycles (354 days) which were rounded up to 360, forming 12 months at 30 days. What differentiated the Sumerian calendar system from any other lunar calendars of this time, was the way they measured time. The Sumerian calculations are all heavily based on the numbers 6, 12 and 60, still used today.  Our current year has 12 months and the day in many countries is structured as 12 hours am and 12 hours pm. The hour itself has 60 minutes and every minute has 60 seconds.

To bring the shortfall of these embellished lunar months into sync with the solar year, the equinoxes (where day equals night) and the solstices (longest and shortest day of the year), the Sumerian astronomers introduced an extra month every four years. This is what we now call a leap year.

The Sumerians also recorded ‘day qualities’. Enuma Anu Enlil is a collection of stone tables and oracles compiled by Sumerian and Assyrian scribes.  The tables include information about lunar eclipses, weather events, the movement of the stars, planets and constellations. The most important part was the interpretations of all these cosmic movements and what they meant for life on earth. The dominant observations concerned the moon cycle and its relation to the other stars and the sun.

 It is still unclear where all this knowledge came from. But what is certain that it helped to shape the later famous Babylonian calendar. Although these were humble beginnings, these scribes crucially laid down the foundation of the houses, the star signs and the creation of the zodiac (called the ‘circle of the animals). They named many star constellations in the sky and created the basic principals of Western astrology. The movements of the planets and stars were meticulously observed, recorded, and interconnected with symbolic meaning. These observations traveled to other countries, particularly to India in the 3rd century B.C.

From 499.B.C. the Sumerian calendar transformed into a proper lunisolar calendar. The shift came when it was recognized that 19 solar years equal exactly 235 lunations (moon cycles) and this formed the first proper re-occurring connection between the solar and the lunar cycle.  This principle was formally described by the Greek astronomer Methon of Athens in 432 B.C. when he ‘discovered’ the Metonic cycle. But most probably he came across the Babylonian calendar and recalculated their calendar formula.

The Sumerian calendar month started at sunset with the first sighting of the new crescent moon (Waxing Moon) and ended with the last sighting of the descending crescent (Waning Moon). Once the Waning moon had vanished there followed a period of the ‘disappeared moon’ (New Moon) when no moon was visible in the sky.

This played a big part when planning to travel, especially crossing a desert. Due to the hot climate caravans preferred to travel at night. But with no moonlight to guide them, there was a great chance of getting lost.  Therefore the New Moon became known as the time to stay at home and rest.  A concept we still use in the LWTM life goal planner.

On the other hand, the moon’s opposite position in the lunar cycle – the Full Moon-  was the time for gatherings and ceremonies. Then people could easily find their way home once it got dark.

The roots of the Sumerian lunisolar calendar still exist today, particularly in many religious calendar systems and associated practices.

The ‘Living With the Moon lifestyle calendar’ is also based on the Ancient Lunisolar Calendar. It is now believed to be much older than the Sumerian Calendar. Some sources suspect it goes all the way back to the Minoan civilization (2700-1450 B.C).

For more information about day qualities, holistic life goal planning and more, please download our LWTM freebees package.