The History of the Western Calendar

THE HISTORY OF THE WESTERN CALENDAR

CREATED BY: NICLAS MARIE

 In the earliest times, human beings calculated
time by observing the periods of light and
darkness that alternated continuously. The
solar day is considered the earliest form of
the calendar. The second basic type of
calendar was the arbitrary calendar, which
was created by counting the number of days
over and over again, either towards infinity
or in a cycle.

 Nonetheless, there were several problems with the
arbitrary calendar. Firstly, farmers of early civilizations
could not calculate the perfect time to plant their
crops. Crop planting is an activity that is closely linked
to the seasons, and the arbitrary calendar was not
based on the durations of seasons. Therefore, humans
began to observe the sun’s passage through a fixed
point, and this practice was the precursor of the solar
calendar. Calendars that were based on lunar and
stellar cycles were also used in the ancient times.

EARLIER HISTORICAL CALENDARS

 One of the first truly scientific calendars was the
Egyptian calendar. According to this calendar, a year
comprised of 12 months, and each month had exactly
30 days. The months were further divided into three
weeks, with each week lasting 10 days. Later on, the
Babylonian calendar was developed, and it was a
lunisolar calendar. The years in this calendar were made
up of 12 lunar months, and each month would begin
when a new crescent moon appeared.

 The Greeks used a calendar that was very similar to
the Babylonian calendar, but they also had other
calendars, such as the democratic state calendar with
10 arbitrary months and an agricultural calendar. The
first Roman calendar was created by Romulus, and it
had 10 months in a year, with each month lasting 30 or
31 days. The Romans had a number of calendars, and
the most notable one was the Julian calendar. The
Jewish calendar was another early type of calendar, and
it contained no epagomenal days. The seventh day was
called Sabbath.

THE JULIAN CALENDAR

 The Julian calendar was introduced in 45 BC by
Julius Caesar. Although it had 12 months, many of
its months were shorter than the months in the
modern calendar. As such, one Julian year only
consisted of 355 days. Before Julius Caesar’s
reforms, the year began on the 31st of March. A
leap month with 23 or 24 days was also created
to keep the calendar properly aligned with the
cycle of seasons.

 The Roman calendar also had a recurring cycle of
weeks that is similar to the modern cycle, but each
week comprised of eight days. Julius Caesar brought
in a number of reforms to the old Roman calendar.
One of them was the addition of days to February
to make it a 28-day month. The week was also
reduced by one day to make it a 7-day week.
Additionally, Caesar introduced the leap year rule,
which stated that all leap years can be evenly
divided by four.

THE CALCULATION OF EASTER

 In his seminal work Ecclesiastical History of the English, the historian
Bede described how the Roman Church and Irish Church had divided
opinions on the calculation of Easter. At the synod of Wilby, King
Oswy heard both sides of the argument and finally decided to vote for
the Roman method, which suggested that Easter Day should fall on
the first Sunday after the paschal full moon.

 The influence of the powerful Roman Church of the 14th century
also ensured that most European regions adopted the Roman
calculation. It was during this time that the “Anno Domini” dating,
or “AD”, was implemented. Anno Domini is the counting of years
from the time of Jesus Christ’s incarnation.

THE GREGORIAN CONVERSION

 In the year 1582, Pope Gregory XIII decreed that there should be a
change in the Julian calendar. The Gregorian calendar was a theoretical
calendar, and it was created from very precise calculations of vernal
equinoxes. The Julian calendar was based on the assumption that the
duration between vernal equinoxes is 365 ¼ days, but in reality, it is
approximate ly 11 minutes less.

 As such, the Gregorian calendar had three leap days removed every four hundred years. Also, changes were made
to the lunar cycle, which helped in the calculation of Easter. Many European countries did not adopt the
Gregorian calendar when it was introduced, mainly because of the Protestant Reformation that was taking place
at that time. Nevertheless, by the 20th century, the calendar became the standard calendar in Europe. Today, it is
the most widely used calendar in the world.

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