As the world celebrated January 1, 2020, and coins from countries around the globe start to bear this date, the question is, how did we get to here – 2020? To better understand how the current calendar came into use, a brief review of the Common Era calendar history is in order.
Julius Caesar was the first to reform the calendar into something similar to what we use today. Prior to Caesar, a lunar-based system was used that had 12 months consisting of a total of 355 days, which was dated in cycles in which some years would have up to 378 days. With the reforms that Caesar made, Rome and the world consisting of the Roman Empire moved to a solar-based calendar that followed the sun rather than the moon. This allowed for more consistent yearly calendars. The reform also changed the number of days in a year to 365, with an extra day every four-year cycle to account for the actual time of solar rotation. Caesar also reformed the start of the year to January 1 in his 12-month system. July was named in honor of Julius Caesar after his death. Because Rome adopted this system, those areas which comprised the Roman Empire, including large parts of what is now France and Germany, England, Spain, North Africa, and the Middle East, adopted this system, making it common throughout the Western World.
This new calendar, called the Julian calendar, used the date of the establishment of Rome, 753 BC or BCE (Before Christ or Before the Common Era), as it’s “initiation point.” If the coming of the Christian era had not occurred, we would be in about the year 2773 today, not 2020. What changed this scenario was the establishment of Christianity. Christianity was so pervasive in early Medieval Europe that the denoting of years was split before Christ (BC) and after (the birth of) Christ (AD or “Anno Domini,” in the year of the Lord).
For coins, the first uses of the “Anno Domini,” or AD using the Julian Calendar, began as early as 1234. An entire book, The Early Dated Coins of Europe 1234-1500 by Robert A. Levinson, covers the area comprehensively. Coinage continued to use the Julian Calendar until the next reform.
As the influence of Europe continued to spread, so did the Julian Calendar. From the colonization of the Americas, Africa, Asia, and other areas around the globe occurred by the European powers, their calendar, and dating system was adopted wherever they went. Under the leadership of Pope Gregory XIII, it was determined that corrections were needed to the Julian calendar to align the calendar with the drift that had occurred from the equinoxes during the calendar’s use. Thus in 1582, there was a 10-day shift in dates. And, very important to Catholic Europe, the shift put Easter on the date it should have been celebrated. The Gregorian calendar was adopted immediately by all Catholic countries in Europe and their colonies, but it took almost 300 years for it to be universally adopted around the globe. The Gregorian calendar is the system we use today.
Today most countries use this date on their coinage. Some countries use other calendars and dating systems for internal use and on their coinage. Still, the Common Era or Gregorian calendar has been established as the relative time-telling system it is.