Wall Calendars - Big and Basic

A Short History of our Modern Calendar

They are on the wall, we carry them in our briefcase, purse, shirt pocket. We take them for granted. But like many things we take for granted, the calendar is far more complex and far more important than most of us realize.

When agriculture began to replace hunting and gathering, ancient people needed a way to tell when rivers would flood, when the spring rains would come, and when winter was near. Without a calendar, knowing these things would be nearly impossible. It isn't a stretch to say that the development of the calendar is one of the cornerstones of civilization.

And ancient peoples did amazing things to figure out the time of the year. Stonehenge (UK/Celtic?), Chitzen Itza (Mexico/Myan), the Callanish Standing Stones (Scottland/Celtic?), possibly even the Nasca geoglyphs (Peru/Nasca) and the Pyramids were all "observatories" designed, at least partly, to determine the time of year.

This short article can't possibly cover this much time, but I wanted to emphasize the fact of the importance of the calendar in the development of civilization. Now let's skip ahead to the time of the Romans.

Until the time of the Romans, every group of people had their own system of recording time and their own calendar. Rome, having conquered nearly the entire Mediterranean world and much of Europe was in a unique position to bring some standardization to the calendars then in use.

In 46 BC Julius Caesar reformed the Roman calendar, and the result became known as the Julian Calendar. It introduced the concept of the "leap year," and changed the beginning of the year from the first of March, to the first of January.

The problem that the leap year tried to address is the not so simple fact that a day for the planet earth is not 24 hours long. It is actually 23 hours, 56 minutes and 4 seconds. That's how long it takes a particular spot on earth to rotate around to the exact same position relative to the background stars. Couple this with the fact that an actual year is (using the most modern estimate) 365.24219 days long.

Wow, this is getting complicated. Yes, it is. And the leap year was too simple of a solution. Enter the Gregorian Calendar. In 1582 Pope Gregory decreed that the Julian calendar needed reformed and corrected. Although he was primarily interested in getting the date of Easter "right," still he took the best advice from mathematicians and astronomers, and did make improvements. The most interesting of which (from the average person's point of view) is that 10 whole days were dropped from the calendar in 1582. In lands where the Roman Church held sway, people went to bed on October 4 and woke up on October 15.

To make matters worse, politics and religion were heavily involved. Protestant countries, and other lands that had political issues with the Vatican, did not immediately adopt the Gregorian Calendar. Surprisingly, the last country to adopt the Gregorian Calendar was Greece in 1923.

Obviously, books have been written on this subject, but we have provided this short introduction to (hopefully), spur your interest in a fascinating subject.

Much of the information from the above article came from the following sources:

Gegorian Calendar - Wikipedia
Calendars-Key text
Ancient Observatories
Gregorian Calendar - Calendar Wiki