Calendars' History

All human civilizations knew that a year consisted of roughly 365 days, the length of the cycle the earth required to reproduce grains and fruits in their respective seasons. Festivals and celebrations were designated annually to reflect this phenomena, with Spring recognized as the beginning of a new year, when green is born again after a cold winter's death.

They also observed the moon's cycle, starting with a waxing crescent to a new (black) moon, to be no less than 29 days and no more than 30 days. This meant that one year coincided with the passing of 12 moon cycles (months) and some change. And over time, these months were given names and numbers, to help people keep track of time, which is most useful for farming, the essence of all human economies at the time.

It was known, of course, that 12 moon cycles added up to approximately 355 days, whereas the full solar year was closer to 365 days. So in order to accommodate for those 10 days short, every civilization added a 13th month once every three years (where the 10 days add up to 30 days) to avoid breaking the moon cycle. This 13th month is known as the intercaler month, and when and where to insert it was a major political headache.

The Global (Gregorian) Calendar

In Europe, civilization began in Greece, which had adopted its most basic knowledge (including astronomy) from its neighbors in ancient Syria. The months of course were given Greek names, and it was the Greek empire's successor, Rome, that had spread that tradition to the remainder of Europe, which had adopted the Roman lunar calendar as shown below.

  1. March - from Mars, the god of war.
  2. April - from Aphrodites, the goddess of beauty
  3. May - from Maya, the goddess of fertility
  4. June - from Juno, goddess of marriage
  5. July - from Julius, Caesar of Rome
  6. August - from Augustus, Caesar of Rome
  1. September - from septem, Latin for seven
  2. October - from octo, Latin for 8
  3. November - from novem, Latin for 9
  4. December - from decem, Latin for 10
  5. January - from Janus, the god of gates
  6. February - from Februus, the god of death

The 13th (intercaler) month problem was resolved in Rome by a decree from its first emperor, Julius Caesar, which gave the Roman calendar its new name: the Julian calendar.

Scientists and mathematicians were called to develop a new calendar that no longer depended on moon cycles. After so many versions were adopted (to accommodate certain festivals or political events), starting in 45 BC, the final one remained in use until this day, where each month was given a minimum of 30 days, bringing the total to 360, then adding one more day to each of the five select months. Accurate calculations, of course, showed that a full year was 365 days and 6 hours (¼ of a day). Thus, the four quarters were added up over four years then inserted as one full day at the end of the year: the end of February, the 12th month.

At some point in time, the fifth month was renamed from Quintilis (Latin for 5) to Julius in 44 BC, in honor of the emperor's month of birth. Then the sixth month was renamed from Sextilis (Latin for 6) to Augustus in 8 BC, in honor of Julius Caesar's adopted son and heir to the throne: Augustus Caesar.

As to why February was assigned only 28 days, several theories exist, among them the story of demanding that July and August have 31 days instead of 30, and in order to make that change without affecting the remainder of the carefully calculated and engineered calendar, the last two days of the year were stolen, clearly from February, the last month, to serve that purpose.

Finally, it was Pope Gregory XIII's reform in 1582 AD that dictated that the new year be celebrated in January, not March, to honor the birth of Christ. From that date onward, January became the first month of the year. This calendar, the Gregorian Calendar, has been in use ever since and is still considered the official global calendar.

The Arabic (Hijri) Calendar

In Arabia, the new year was celebrated at the end of the pilgrimage (Hajj) season, which coincided somewhere between August and September in Rome.

  1. Muharram* (مُحَرَّم) - meaning forbidden.
  2. Safar (صَفَر) - meaning emptiness/void
  3. Rabee' 1 (ربيع الأول) - meaning Spring
  4. Rabee' 2 (ربيع الثاني) - ibid.
  5. Jamada 1 (جمادى الأول) - tajammud: freezing
  6. Jamada 2 (جمادى الثاني) - ibid.
* - sacred months; fighting is forbidden.
  1. Rajab* (رجب) - meaning holy
  2. Sha'ban (شعبان) - from tasha'ub; scattering
  3. Ramadhan (رمضان) - from Ramadh; scorching
  4. Shawwal (شَوّال) - "raising" the camel's tail
  5. Thul-Qi'dah* (ذو القِعدَة) - the month of truce
  6. Thul-Hijjah* (ذو الحِجّة) - the Hajj (pilgrimage) season

In 638 AD, Omar ibn al-Khattab, the second caliph (successor) of prophet Muhammad (pbuh), marked the year of Muslim migration (hijra) from Mecca to Medina as year 1 (coinciding with 621 AD). Thus, the Muslim calendar is also known as the Hijri calendar.

The 13th (intercaler) month in Arabia was known as al-Nasee' (النسيء), and the time of its insertion was chosen by Mecca's elders for political advantages. This political problem was resolved by a decree from prophet Muhammad (pbuh), sometime around 630 AD (10 AH), to abolish the intercaler month altogether.

"Indeed, the number of months with God is twelve months in the register of God the day He created the heavens and the earth; of these, four are sacred [the ones underlined in the table]. That is the correct religion, so do not wrong yourselves during them. And fight against the disbelievers collectively as they fight against you collectively. And know that God is with the righteous (36) Indeed, al-Nasee' is an increase in disbelief by which those who have disbelieved are led astray. They make it lawful one year and unlawful another year to correspond to the number made unlawful by God and thus make lawful what God has made unlawful. Made pleasing to them is the evil of their deeds; and God does not guide the disbelievers (37)" Quran - The Repentance (Ch. 9)

Since then, the Arab (now also Muslim or Hijri) lunar year became a free-floating calendar (roughly 355 days) completely independent of the four seasons of the solar year, and the 10 days difference are never adjusted for. This is why Ramadhan, the holy month of fasting, starts 10 days earlier every year.

The names of the 12 months remained the same before and after Islam, except for the first month, which had been called Safar 1 (صَفَر الأوّل), with the second month called Safar 2 (صَفَر الثاني). But since its name was changed to Muharram, the second Safar remained simply as Safar, without a number.

If Muharram (or Safar 1) was originally sometime between August and September, we can then better understand the names chosen for each month. The two Safars (Arabic for void or emptiness) referred to the barren desert. This is also where the word asfar (yellow) comes from, since the barren desert's color is yellow. This meaning is confirmed when the following two months are referred to as Spring 1 and 2, which is when the land is no longer barren, as some grass grows in certain Arab regions (this would be around October and November). Next comes the winter season, when it's coldest, and so the fifth and sixth months are called Jamada 1 and 2, referring to the freezing season, coinciding with December, January, and February. Rajab, the seventh month, was a month of holiness, probably in some Pagan traditions as well, coincided with March.

Hijri Date Converter
Today's Date:
Gregorian Calender
Month Day Year
Hijri/Islamic Calender
Month Day Year

Day of the Week:

Sha'ban (scattering) referred to the time of year when Arab tribes scatter around the lands in search of water, in preparation for the long, hot summer. Indeed, the 9th month, Ramadhan, means the scorching hot month, coinciding with May. The 10th month was called Shawwal in reference to female camels raising their tails. Thul-Qi'dah is another sacred month (before and after Islam), literally meaning "the month of sitting," which is the opposite of "rising" to battle. In this month the Arabs have a truce to make time to prepare for the season of pilgrimage to holy temples, Mecca being one of its greatest locations. In all four sacred months, fighting is forbidden.

The Syriac Calendar

The oldest calendar belongs to the most ancient of all civilizations, the Babylonian/Assyrian Syrian civilization, which covered the area of today's Iraq, Syria, Lebanon, Palestine, Jordan, Cyprus, and parts of Turkey and Persia. The Babylonian (now Syriac) calendar celebrates the new year with the arrival of Spring, the month of Nissan (coincides with March/April). This is why Babylonian horoscopes begin with Aries (starting March 22 today).

The Syriac calendar is still in use today (both officially and colloquially) in Iraq, Syria, Lebanon, Palestine, and Jordan, although their original meanings have been forgotten. These Syriac month names have become the Arabic translation of the Gregorian (global) months, with Nissan standing for April, both of which have become the 4th month of the year.

  1. Nissan (ܢܝܣܢ) - Beginning, Lawn.
  2. Ayyar (ܐܝܪ) - Light.
  3. Huzayran (ܚܙܝܪܢ) - Wheat, season of harvest
  4. Tammouz (ܬܡܘܙ) - a god's name: Son of Life.
  5. Aab (ܐܒ) - Ripeness, of fruit.
  6. Ayloul (ܐܝܠܘܠ) - Wailing, the death of Tammouz.
  1. Tishreen 1 (ܬܫܪܝܢ ܐ) - Autumn 1.
  2. Tishreen 2 (ܬܫܪܝܢ ܒ) - Autumn 2.
  3. Kanoon 1 (ܟܢܘܢ ܐ) - Inertia 1.
  4. Kanoon 2 (ܟܢܘܢ ܒ) - Inertia 2.
  5. Shubaat (ܫܒܛ) - Strike, caused by strong winds.
  6. Athar (ܐܕܪ) - Loudness, caused by violent storms.

The Ecclesiastic (Christian) Calendar

Coming Soon.

The Jewish Calendar

The names of the months in the Jewish calendar were copied from the Babylonian (Aramiac-Syriac) names, also starting with Nissan (roughly March/April) with the Spring season. It is believed that this copying of month names happened after the Jews were exiled to Babylon (before then, the Jewish months only had numbers). However, they celebrate their new year (rosh hashanah) on the start of the seventh month (Tishri), which usually coincides with September/October in the global calendar.

As the Jewish calendar is lunar, the intercaler (thirteenth) month is inserted approximately once every three years. It is inserted before the last month (Adar), but it is also called Adar. To distinguish between the two in a leap year, the inserted month becomes Adar 1 (or Adar alef), and the final month becomes Adar 2 (or Adar beit).

  1. Nissan (ניסן) - Beginning from Syriac Nissan
  2. Iyar (אייר) - Light= from Syriac Ayyar
  3. Sivan (סִיוָן) - Season of harvest, from Akkadian Simanu.
  4. Tammuz (תמוז) - a god's name: Son of Life, from Syriac Tammouz
  5. Av (אָב) - Ripeness of fruitsm from Syriac Ab.
  6. Elul (אֱלוּל) - Wailing the death of Tammuz, from Syriac Ayloul.
  1. Tishri (תשרי) - Autumn from Babylonian Tishri.
  2. Cheshvan (חשון) - The Eighth Month, from Akkadian Marcheshvan
  3. Kislev (כִּסְלֵו) - Plentiful of rain, from Akkadian "kislimu"
  4. Tevet (טבת) - Goodness, from Syriac Tebet.
  5. Shevat (שְׁבָט) - Strike of winds, from Syriac Shubaat.
  6. Adar (אֲדָר) - Loudness of the storm, from Syriac Athar.

The Chinese Calendar

Coming Soon.