The Gregorian Calendar is increasingly used for commerce
world-wide. It is based upon the earlier Julian Calendar which
was designed by Pagan priests in Rome circa 50 BCE. Julius
Caesar had asked them to design a calendar that was more accurate than the ones
which were in use at the time. During the Christian era, the calendar was
adjusted so that DEC-25 of the year 1 BCE was believed to be the birthday of
Jesus Christ. Today, most Christian theologians believe that Jesus was born sometime
between 4 and 7 BCE, probably in the fall of the year.
Unfortunately, the Julian calendar was too long by about 11 minutes and 14
seconds each year, or one day every 128 years. By the late 16th century, this
error had accumulated to an intolerable 10 days. Pope Gregory XIII commissioned
a study to decide how to correct it and how to prevent it from drifting in the
future. The solution was to make most of the century years into non-leap years;
only those which were evenly divisible by 400 (e.g. 1600, 2000, 2400 etc.) were
to be leap years. Roman Catholic countries corrected the calendar by making
1582-OCT-15 CE follow OCT-4. In England, they made an 11
day correction; the day following 1752-SEP-2 was SEP-14. Riots were widespread among the public because many believed that they had lost 10 or 11 days of life. Greece did not convert
to the Gregorian calendar until 1923.
There remain many religiously based calendars which are different from the
Gregorian calendar. Some are:
Most Eastern Orthodox Churches continue to use the Julian calendar. It
is currently 13 days later than the Gregorian calendar. The gap continues to grow. When measured by the Gregorian calendar, they
currently celebrate Christmas on JAN-7 and New Year's Day on January 14 .
Romanian and Greek Orthodox do not follow this tradition.
Buddist calendars vary according to location. In Thailand, the Gregorian Calendar was adopted on 1941-JAN-01 except that the year numbering was altered. The starting year was 2484 BE, and was based on the estimated year the death of Gautama Buddha. . "Since that date, the Thai Buddhist Era "BE" equals that of the Gregorian Calendar (CE) plus 543 years. Wikipedia describes a number of other Buddhist Calendars. 4
The Jewish calendar is based on an estimate of the start of human civilization which they believe began with the exit of Adam and Eve from the Garden of Eden during 3761 BCE. The abbreviation "AM"
for Anno Mundi is used. The Jewish calendar is moon-based. An additional
month is added every third or fourth year. Thus, their year is of 354 to 385
days in duration.
The Islamic calendar is based upon 622 CE, the year
of the Hegira, when the Prophet Muhammad traveled from Mecca to Medina. The abbreviation "H" or "AH"
is used after the date; it stands for "Hegira" or "Anno Hejira". It is
a lunar calendar that repeats itself every 30 years. Year 2, 5, 7, 10, 13, 16, 18, 21, 24,
26 and 29 are leap years and have 355 days. Common (non leap years) have 354 days. That is
11 days shorter than the solar year. When measured by the Gregorian calendar, about three times a century, Muslims can celebrate
two new years. In some countries, each lunar month begins with the
visible sighting of the crescent of the new moon. A month, and thus a
holy day, is often delayed a day from the time that astronomical
calculations would predict them. Other countries use a calculated date for the new moon and don't rely on sightings.
The Hindu calendar is based upon the start of the Saka Era in 78 CE.
The date is often followed by the letters SE. The original
base date for the calendar was at a planetary alignment involving Jupiter in
The Sikh calendar is based on the start of the Khalsa Era three
centuries ago. Their year begins on Apr-13 or 14. The date is often followed by the
The Baha'i calendar began when the Bab declared that a new
Manifestation of God would shortly appear. The beginning of the Baha'i Era occurred in
1260 AH which is 1844 CE. Their calendar has 19 months, each with 19 days, for a total of 361
days per year. The letters BE stand for "Baha'i Era."
The traditional Zoroastrian calendar is composed of 12 months, each
containing 30 days. The final month has 5 "gatha" days added. Initially, an
additional month of 30 days was added once every 120 years. The base year
for the calendar is the date of the coronation of the last Zoroastrian
Sasanian King, Yazdegird II in 631 CE. 1368 Y overlaps 1999 CE. The Iranian
Zoroastrians stopped adding this additional month in 1009 CE; Their fellow
believers in India stopped in 1129 CE. New Year has been gradually moving
earlier (about 1 day every 4 years) from its original date in mid-March. It
now occurs in the Fall. Mr. Khurshedji Cama proposed a revised calendar in
1906 CE. It follows the Gregorian leap-year system and has New Year
permanently fixed on MAR-21. This calendar is used by Zoroastrians around
the world, except India. 8
The Creativity Movement (formerly called the World Church of the Creator (W.C.O.T.C.) is a racist,
anti-communist, and homophobic religious group centered in Illinois.
They base their calendar on 1973 CE --the date that the first edition
of their book "Nature's Eternal Religion" was
published. This is regarded as the year in which the group was
founded. They have abandoned the Gregorian calendar. 1973 is
considered the Incepto de Creativitat (Inception of
Creativity), or I.C. Years following are called "Anno de
Creativitat." Thus, 1974 CE is called 1 A.C. The years before
I.C. are called Prius Creativitat (Before Creativity). One of their
main holidays is West Victory Day, held each DEC-29. It
commemorates the "white" victory
over the last organized resistance during the Native American genocide in 83 PC (1890 CE).
The Church of Satan was organized by Anton La Vey (1930-1997) in the year 1966. He defined that as "the year One", Anno Satanas—the first year of the Age of Satan. His calendar uses the Gregorian Calendar, but renumbers the years. Year 2011 in the Gregorian Calendar is year XLVI A.S. So, they observed Halloween that year on OCT-31, XLVI A.S.
The Mayan calendar expresses
a date in a complex five number format. e.g. 188.8.131.52.5 means:
6 Baktun, an interval of 144,000 days (almost 400 years),
19 Katun (generations) of 7200 days (almost 20 years),
18 Tun (years) of 360 days,
1 Uinal (month) of 20 days,
5 Kin (days)
for a total of 1,007,305 days.
J.Eric Thompson determined that the first day of the Mayan calendar
(0.0.0.0.0) was on 3114-AUG-11 BCE. 9 They
believed that the planet Venus was born on that day. Another source says AUG-13 of the
same year. Mayans also had a "Great Cycle of the Long Count"
of 13 Baktuns or 5,125.36 years. There are many books written in anticipation of the end
of the world at the Winter
Solstice, 2012-DEC-21 or 184.108.40.206.0 in the Mayan notation. 10 This appears to be a hoax generated by a group of authors who have combined the end of the world scenario found in the Abrahamic religions (Judaism, Christianity and Islam) with the Mayan belief in a cyclical, repeating universe. According to records left by the Mayan the only event expected on that day is the return of a god-man to Earth. There are hundreds of glyphs that predict various other events happening after the end of 2012.
The first day of various religious years fell on the following dates in 1996-1997 in the Gregorian Calendar:
Secularists, western Christianity, etc.
Church of Satan
2539 BE (Buddhist Era)
Thai solar calendar (Buddhism)
Eastern Orthodox (most)
Wiccan (at sunset, Samhain)
153 BE (Baha'i era)
* Approximate date.
** Except in the Middle East
JewishGen® provides a guide to Jewish genealogical research. One service is an online
calendar that converts Gregorian to Jewish dates and back. For example St. Patrick's day
on 1999-MAR-17 is also 5759 Adar(I) 29.1 Another web site,
Panda Systems, offers a free calendar conversion program for the MacOS which works among
Julian, Gregorian and Jewish calendar systems. 2