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The Origin Story – Calendars

Team StoryWeavers|June 08, 2022, 08:39 IST| 5

Have we always counted days, weeks and months the way that we do now? Why do we use the calendar that we use today or what drove us to have a 365-day year? Why do we celebrate the first day of January as New Year? If you have asked yourself these questions in the past, then you would want to read on because, in this edition of The Origin Story, we are going to unfurl the story of the Calendar.

Calendars around the world

The calendar was first used more than 3000 years ago during the Bronze age. Back then, it was just a timekeeping method but now we have it conveniently built into our phones to help us organise our days in a better fashion. We set up reminders on our calendars so that we can wish our loved ones on their special days, finish our assignments prior to deadlines and much more. 

The origin of the calendar involves astronomy, religion and history. Ancient calendars were based on the phases of the moon and the solar year. There have been hundreds of calendars throughout history. Various cultures have developed calendars such as the Hebrew calendar, the Egyptian Calendar, the Greek Calendar, the Chinese Calendar, the Babylonian Calendar among many others. Some of them are still in use even to this day.

In India, we have various religious and cultural communities celebrating the new year based on lunar and solar calendars. The new year is often celebrated as a harvest festival by these communities. We have the Malayalee community celebrating Vishu to mark the beginning of ‘Medam’, the ninth month in the solar calendar followed in Kerala. People from Karnataka, Telengana and Andrapradesh commemorate Ugadi, the first day of the Hindu lunisolar calendar (a calendar that indicates both the moon phase and the time of the solar year)  month of Chaitra. Bengalis observe Pohela Boishakh on the first day of Vaishakh, which is the Bengali new year. Muslims follow the lunar Hijri calendar and they celebrate their new year on the first day of Muharram. All these festivals mark new beginnings and are celebrated with the right degree of pomp and show.

Chinese communities across the world also celebrate the Chinese New year, an annual 15-day festival. It is also known as the lunar new year as the festivities begin with the new moon and last till the following new moon. It usually falls between January 21 and February 20.

The Roman Calendar

Would you believe us if we told you there were only 30 days in December at some point in time? Well, December had only 30 days in the Roman calendar and the calendar year lasted only 304 days. The calendar that we use today originated from the Roman calendar dated 753 BC. The names of months of the modern day calendar have been derived from the Roman calendar. The Roman calendar was a lunar one comprising ten months and 61 days of winter not assigned to any month. Unlike today, the Roman calendar began with March. The months were named Martius, Aprillis, Maius, Junius, Quintilis, Sextilis, September, October, November, and December. Later in 703 BC, Numa Pompilius, the second King of Rome, added Januarius and Februarius to make a twelve-month or 355-day year in 703 BC.

The Julian Calendar

Before Julius Ceasar became the emperor of the Roman empire, the calendar was being manipulated by the Roman high priest for several reasons. Sometimes years were lengthened to keep allies in office and sometimes they were shortened to eliminate rivals. Julius Caesar put a stop to all that by introducing the Julian Calendar in 45 BCE.

Did you know our revolution around the sun is not a perfect 365 days but 365 days, 5hours, 48 minutes and 46 seconds?

Julius Caesar adopted the solar year which had 365.25 days. The four-year leap year cycle was added to resolve the 25th of a day. The reforms took place on January 1, 45 BCE. This changed the beginning of the year from March 1st to January 1st. Since then, we have been celebrating New Year’s on January 1. The Romans had an eight-day week cycle but eventually, astrologers assigned a planet to the 24 hours of the day in a continual sequence. This led to the roman seven-day cycle. Saturn, The Sun, Moon, Mars, Mercury, Jupiter and Venus became Saturday, Sunday, Monday, Tuesday, Wednesday, Thursday and Friday.

The Julian Calendar was mostly perfect. However, the church was not too keen on using the Julian Calendar. Here’s why.

The 365.25 day year is 11 minutes and 15 seconds longer than the true length of the tropical year. Even though it might seem like a negligible difference, it adds up over time. So much so that after 128 years, the season begins an entire year early!

Why the Gregorian Calendar?

The calendar we use today is called the Gregorian calendar and it is the most widely used calendar in the world. It is named after Pope Gregory XIII as it was implemented by him in 1582. The reason the pope was so interested in the calendar is that it affected when Christians got to celebrate Easter. Easter was supposed to fall on the Sunday after the first full moon, after the March equinox -the time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of approximately equal length – ideally on March 21 but it fell further away with every passing year. 

An old sculpture of Pope Gregory XIII in Bologna, Italy.

To ensure that Easter would be celebrated at the same time of the year as it historically had, Pope Gregory adjusted the rules for which years would be leap years. As with the Julian Calendar, a leap year would happen every 4 years except for years that are divisible by 100. But the years that are divisible by 400 are also leap years. For example, the years 1800 and 1900 were not leap years but 2000 was (2000 is divisible by 400). The changes Pope Gregory established resolved the shift at the beginning of the year and set a standard for the length of a year in days, minutes, and seconds.

The changes were not accepted by many societies. For this reason, the timeline of historical figures will have two dates, the Gregorian(new style) and Julian(old style). The only difference between the two calendars is the way they dealt with leap years.

Which calendar would you rather follow? Gregorian or Julian? Are there any other regional calendars that are used at your home? Tell us in the comments below.

Leave a Comment



Uday Raj Khatri

December 27, 2020

Calendar is really an amazing thing, just a piece of paper helps us experience important days

Anuj Sikarwar

December 26, 2020



December 25, 2020

For official purposes, Gregorian calendar is used
But at our home, for festivities, fasts and other occasions we refer to our traditional Panchang

Parvathi Ajayakumar

December 25, 2020


Satyam Chauhan

December 24, 2020

At our home we use the Gregorian Calendar as well as the Hindu calendar.


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