Calendar era
Encyclopedia
A calendar era is the year numbering system used by a calendar
. For example, the Gregorian calendar
numbers its years in the Western Christian era (the Coptic and Ethiopic churches have their own Christian eras, see below). The instant, date, or year from which time is marked is called the epoch
of the era. There are many different calendar eras.
In antiquity, regnal year
s were counted from the ascension of a monarch. This makes the Chronology of the ancient Near East
very difficult to reconstruct, based on disparate and scattered king lists, such as the Sumerian King List
or the Babylonian Canon of Kings
. In East Asia, reckoning by era names chosen by ruling monarchs ceased in the 20th century, except for Japan, where they are still used.
This system was in use from the 4th century BC until the 3rd or 4th century AD.
cycle (15 indictions made up an agricultural tax cycle, an indiction being a year in duration). Documents and events began to be dated by the year of the cycle (e.g., "fifth indiction", "tenth indiction") in the 4th century, and was used long after the tax was no longer collected. This system was used in Gaul
, in Egypt
, and in most parts of Greece until the Islamic conquest, and in the Eastern Roman Empire until its conquest in 1453. The rule for computing the indiction with his newly-invented years AD was stated by Dionysius Exiguus
: add 3 and divide by 15; the remainder is the indiction, with 0 understood to be the fifteenth indiction. Thus 2001 was the ninth indiction. The beginning of the year varied.
, called the Era of Contracts by Jews, formerly used in much of the Middle East from the 4th century BC to the 6th century AD, dates from the epoch 312 BC, August of that year being when Seleucus I Nicator
captured Babylon
and began his reign over the Asian portions of Alexander the Great's empire. Thus depending on whether the calendar-year is accorded as beginning from 1 Tishri or from 1 Nisan, the Seleucid era begins in either 311 BC (the Jewish reckoning) or in 312 BC (the Greek reckoning). The Seleucid era is mentioned in the Hebrew Bible
in the Book of Maccabees
.
ar' dating. This involved naming both consules ordinarii who had taken up this office on January 2 of the civil year. Sometimes one or both consuls might not be appointed until November or December of the previous year, and news of the appointment may not have reached parts of the Roman empire for several months into the current year; thus we find the occasional inscription where the year is defined as "after the consulate" of a pair of consuls.
The use of consular dating ended in 541 when the emperor Justinian I
discontinued appointing consuls. The last consul nominated was Anicius Faustus Albinus Basilius
. Soon after, imperial regnal dating was adopted in its place.
, which is the title of T. Livy's history of Rome.)
Several epochs were in use by Roman historians. Modern historians usually adopt the epoch of Varro
, which we place in 753 BC.
The system was introduced by Marcus Terentius Varro
in the 1st century BC. The first day of its year was Founder's Day (April 21), although most modern historians assume that it coincides with the modern historical year (January 1 to December 31). It was rarely used in the Roman calendar
and in the early Julian calendar — naming the two consul
s that held office in a particular year was dominant. is the same as AUC ( + 753).
About AD 400, the Iberian historian Orosius used the AUC era. Pope Boniface IV (about AD 600) may have been the first to use both the AUC era and the Anno Domini era (he put AD 607 = AUC 1360).
of the Roman emperor
. At first, Augustus would indicate the year of his rule by counting how many times he had held the office of consul, and how many times the Roman Senate
had granted him Tribunican
powers, carefully observing the fiction that his powers came from these offices granted to him, rather than from his own person or the many legion
s under his control. His successors followed his practice until the memory of the Roman Republic
faded (late in the 2nd century or early in the 3rd century), when they openly began to use their regnal year.
dated their calendars from the date of Roman conquest, or the establishment of Roman rule.
The Spanish era
counted the years from 38 BC, probably the date of a new tax imposed by the Roman Republic on the subdued population of Iberia. The date marked the establishment of Roman rule in Spain and was used in official documents in Portugal, Aragon
, Valencia
, and in Castile
, into the 14th century.
Throughout the Roman and Byzantine periods, the Decapolis
and other Hellenized cities of Syria and Palestine used the Pompeian era
, counting dates from the Roman general Pompey
's conquest of the region in 63 BC.
s were also important, for example the year from the foundation of one particular city, the regnal year of the neighboring Persian emperor, and eventually even the year of the reigning Caliph
.
to the Early Middle Ages
, roughly between the 6th and 10th centuries.
of Christ
was introduced by Dionysius Exiguus
in 525 and is in continued use with various reforms and derivations. The distinction between the Incarnation being the conception or the Nativity of Jesus
was not drawn until the late ninth century. The beginning of the numbered year varied from place to place; when, in 1600, Scotland adopted January 1 as the date the year number changes, this was already normal in continental Europe. England adopted this practice in 1752.
Calendar
A calendar is a system of organizing days for social, religious, commercial, or administrative purposes. This is done by giving names to periods of time, typically days, weeks, months, and years. The name given to each day is known as a date. Periods in a calendar are usually, though not...
. For example, the Gregorian calendar
Gregorian calendar
The Gregorian calendar, also known as the Western calendar, or Christian calendar, is the internationally accepted civil calendar. It was introduced by Pope Gregory XIII, after whom the calendar was named, by a decree signed on 24 February 1582, a papal bull known by its opening words Inter...
numbers its years in the Western Christian era (the Coptic and Ethiopic churches have their own Christian eras, see below). The instant, date, or year from which time is marked is called the epoch
Epoch (reference date)
In the fields of chronology and periodization, an epoch is an instance in time chosen as the origin of a particular era. The "epoch" then serves as a reference point from which time is measured...
of the era. There are many different calendar eras.
In antiquity, regnal year
Regnal year
A regnal year is a year of the reign of a sovereign, from the Latin regnum meaning kingdom, rule.The oldest dating systems were in regnal years, and considered the date as an ordinal, not a cardinal number. For example, a monarch could have a first year of rule, a second year of rule, a third, and...
s were counted from the ascension of a monarch. This makes the Chronology of the ancient Near East
Chronology of the ancient Near East
The chronology of the Ancient Near East provides a framework of dates for various events, rulers and dynasties. Individual inscriptions and texts customarily record events in terms of a succession of officials or rulers, taking forms like "in the year X of king Y". Thus by piecing together many...
very difficult to reconstruct, based on disparate and scattered king lists, such as the Sumerian King List
Sumerian king list
The Sumerian King List is an ancient manuscript originally recorded in the Sumerian language, listing kings of Sumer from Sumerian and neighboring dynasties, their supposed reign lengths, and the locations of "official" kingship...
or the Babylonian Canon of Kings
Canon of Kings
The Canon of Kings was a dated list of kings used by ancient astronomers as a convenient means to date astronomical phenomena, such as eclipses. The Canon was preserved by the astronomer Claudius Ptolemy, and is thus sometimes called Ptolemy's Canon. It is one of the most important bases for our...
. In East Asia, reckoning by era names chosen by ruling monarchs ceased in the 20th century, except for Japan, where they are still used.
Olympiad dating
Among the ancient Greeks, a common method for indicating the passage of years was based on the order of Olympic Games, first held in 776 BC. The pan-Hellenic games provided the various independent city-states a mutually recognizable system of dates. The first Olympiad also marks the traditional beginning of Greek historical civilization and record-keeping, and it continues to be regarded as the end of Western prehistory and the beginning of its historical epoch.This system was in use from the 4th century BC until the 3rd or 4th century AD.
Indiction cycles
Another common system was to use the indictionIndiction
An indiction is any of the years in a 15-year cycle used to date medieval documents throughout Europe, both East and West. Each year of a cycle was numbered: first indiction, second indiction, etc...
cycle (15 indictions made up an agricultural tax cycle, an indiction being a year in duration). Documents and events began to be dated by the year of the cycle (e.g., "fifth indiction", "tenth indiction") in the 4th century, and was used long after the tax was no longer collected. This system was used in Gaul
Gaul
Gaul was a region of Western Europe during the Iron Age and Roman era, encompassing present day France, Luxembourg and Belgium, most of Switzerland, the western part of Northern Italy, as well as the parts of the Netherlands and Germany on the left bank of the Rhine. The Gauls were the speakers of...
, in Egypt
Egypt
Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...
, and in most parts of Greece until the Islamic conquest, and in the Eastern Roman Empire until its conquest in 1453. The rule for computing the indiction with his newly-invented years AD was stated by Dionysius Exiguus
Dionysius Exiguus
Dionysius Exiguus was a 6th-century monk born in Scythia Minor, modern Dobruja shared by Romania and Bulgaria. He was a member of the Scythian monks community concentrated in Tomis, the major city of Scythia Minor...
: add 3 and divide by 15; the remainder is the indiction, with 0 understood to be the fifteenth indiction. Thus 2001 was the ninth indiction. The beginning of the year varied.
Seleucid era
The Seleucid eraSeleucid era
The Seleucid era was a system of numbering years in use by the Seleucid Empire and other countries among the ancient Hellenistic civilizations. The era dates from the return of Seleucus I Nicator to Babylon in 311 BC after his exile in Ptolemaic Egypt, considered by Seleucus and his court to mark...
, called the Era of Contracts by Jews, formerly used in much of the Middle East from the 4th century BC to the 6th century AD, dates from the epoch 312 BC, August of that year being when Seleucus I Nicator
Seleucus I Nicator
Seleucus I was a Macedonian officer of Alexander the Great and one of the Diadochi. In the Wars of the Diadochi that took place after Alexander's death, Seleucus established the Seleucid dynasty and the Seleucid Empire...
captured Babylon
Babylon
Babylon was an Akkadian city-state of ancient Mesopotamia, the remains of which are found in present-day Al Hillah, Babil Province, Iraq, about 85 kilometers south of Baghdad...
and began his reign over the Asian portions of Alexander the Great's empire. Thus depending on whether the calendar-year is accorded as beginning from 1 Tishri or from 1 Nisan, the Seleucid era begins in either 311 BC (the Jewish reckoning) or in 312 BC (the Greek reckoning). The Seleucid era is mentioned in the Hebrew Bible
Hebrew Bible
The Hebrew Bible is a term used by biblical scholars outside of Judaism to refer to the Tanakh , a canonical collection of Jewish texts, and the common textual antecedent of the several canonical editions of the Christian Old Testament...
in the Book of Maccabees
1 Maccabees
The First book of Maccabees is a book written in Hebrew by a Jewish author after the restoration of an independent Jewish kingdom, about the latter part of the 2nd century BC. The original Hebrew is lost and the most important surviving version is the Greek translation contained in the Septuagint...
.
Consular dating
An early and common practice was Roman 'consulConsul
Consul was the highest elected office of the Roman Republic and an appointive office under the Empire. The title was also used in other city states and also revived in modern states, notably in the First French Republic...
ar' dating. This involved naming both consules ordinarii who had taken up this office on January 2 of the civil year. Sometimes one or both consuls might not be appointed until November or December of the previous year, and news of the appointment may not have reached parts of the Roman empire for several months into the current year; thus we find the occasional inscription where the year is defined as "after the consulate" of a pair of consuls.
The use of consular dating ended in 541 when the emperor Justinian I
Justinian I
Justinian I ; , ; 483– 13 or 14 November 565), commonly known as Justinian the Great, was Byzantine Emperor from 527 to 565. During his reign, Justinian sought to revive the Empire's greatness and reconquer the lost western half of the classical Roman Empire.One of the most important figures of...
discontinued appointing consuls. The last consul nominated was Anicius Faustus Albinus Basilius
Anicius Faustus Albinus Basilius
Anicius Faustus Albinus Basilius was a high official of the Eastern Roman Empire and the last consul of Roman history, holding the office in 541.- Biography :...
. Soon after, imperial regnal dating was adopted in its place.
Dating from the founding of Rome
Another method of dating, rarely used, was anno urbis conditae (Latin: "in the year of the founded city" (abbreviated AUC), where "city" meant Rome). (It is often incorrectly given that AUC stands for ab urbe conditaAb urbe condita
Ab urbe condita is Latin for "from the founding of the City ", traditionally set in 753 BC. AUC is a year-numbering system used by some ancient Roman historians to identify particular Roman years...
, which is the title of T. Livy's history of Rome.)
Several epochs were in use by Roman historians. Modern historians usually adopt the epoch of Varro
Varro
Varro was a Roman cognomen carried by:*Marcus Terentius Varro, sometimes known as Varro Reatinus, the scholar*Publius Terentius Varro or Varro Atacinus, the poet*Gaius Terentius Varro, the consul defeated at the battle of Cannae...
, which we place in 753 BC.
The system was introduced by Marcus Terentius Varro
Marcus Terentius Varro
Marcus Terentius Varro was an ancient Roman scholar and writer. He is sometimes called Varro Reatinus to distinguish him from his younger contemporary Varro Atacinus.-Biography:...
in the 1st century BC. The first day of its year was Founder's Day (April 21), although most modern historians assume that it coincides with the modern historical year (January 1 to December 31). It was rarely used in the Roman calendar
Roman calendar
The Roman calendar changed its form several times in the time between the founding of Rome and the fall of the Roman Empire. This article generally discusses the early Roman or pre-Julian calendars...
and in the early Julian calendar — naming the two consul
Consul
Consul was the highest elected office of the Roman Republic and an appointive office under the Empire. The title was also used in other city states and also revived in modern states, notably in the First French Republic...
s that held office in a particular year was dominant. is the same as AUC ( + 753).
About AD 400, the Iberian historian Orosius used the AUC era. Pope Boniface IV (about AD 600) may have been the first to use both the AUC era and the Anno Domini era (he put AD 607 = AUC 1360).
Regnal years of Roman emperors
Another system that is less commonly found than thought was to use the regnal yearRegnal year
A regnal year is a year of the reign of a sovereign, from the Latin regnum meaning kingdom, rule.The oldest dating systems were in regnal years, and considered the date as an ordinal, not a cardinal number. For example, a monarch could have a first year of rule, a second year of rule, a third, and...
of the Roman emperor
Roman Emperor
The Roman emperor was the ruler of the Roman State during the imperial period . The Romans had no single term for the office although at any given time, a given title was associated with the emperor...
. At first, Augustus would indicate the year of his rule by counting how many times he had held the office of consul, and how many times the Roman Senate
Roman Senate
The Senate of the Roman Republic was a political institution in the ancient Roman Republic, however, it was not an elected body, but one whose members were appointed by the consuls, and later by the censors. After a magistrate served his term in office, it usually was followed with automatic...
had granted him Tribunican
Tribune
Tribune was a title shared by elected officials in the Roman Republic. Tribunes had the power to convene the Plebeian Council and to act as its president, which also gave them the right to propose legislation before it. They were sacrosanct, in the sense that any assault on their person was...
powers, carefully observing the fiction that his powers came from these offices granted to him, rather than from his own person or the many legion
Roman legion
A Roman legion normally indicates the basic ancient Roman army unit recruited specifically from Roman citizens. The organization of legions varied greatly over time but they were typically composed of perhaps 5,000 soldiers, divided into maniples and later into "cohorts"...
s under his control. His successors followed his practice until the memory of the Roman Republic
Roman Republic
The Roman Republic was the period of the ancient Roman civilization where the government operated as a republic. It began with the overthrow of the Roman monarchy, traditionally dated around 508 BC, and its replacement by a government headed by two consuls, elected annually by the citizens and...
faded (late in the 2nd century or early in the 3rd century), when they openly began to use their regnal year.
Dating from the Roman conquest
Some regions of the Roman EmpireRoman Empire
The Roman Empire was the post-Republican period of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean....
dated their calendars from the date of Roman conquest, or the establishment of Roman rule.
The Spanish era
Spanish era
The Spanish era, Hispanic era or Caesar era refers to the dating system used in Hispania until the 14th century, when the Anno Domini system was adopted. It began with year one in what is 38 BC, probably the date of a new tax imposed by the Roman Republic on the subdued population of Iberia....
counted the years from 38 BC, probably the date of a new tax imposed by the Roman Republic on the subdued population of Iberia. The date marked the establishment of Roman rule in Spain and was used in official documents in Portugal, Aragon
Kingdom of Aragon
The Kingdom of Aragon was a medieval and early modern kingdom in the Iberian Peninsula, corresponding to the modern-day autonomous community of Aragon, in Spain...
, Valencia
Kingdom of Valencia
The Kingdom of Valencia , located in the eastern shore of the Iberian Peninsula, was one of the component realms of the Crown of Aragon. When the Crown of Aragon merged by dynastic union with the Crown of Castile to form the Kingdom of Spain, the Kingdom of Valencia became a component realm of the...
, and in Castile
Crown of Castile
The Crown of Castile was a medieval and modern state in the Iberian Peninsula that formed in 1230 as a result of the third and definitive union of the crowns and parliaments of the kingdoms of Castile and León upon the accession of the then King Ferdinand III of Castile to the vacant Leonese throne...
, into the 14th century.
Throughout the Roman and Byzantine periods, the Decapolis
Decapolis
The Decapolis was a group of ten cities on the eastern frontier of the Roman Empire in Judea and Syria. The ten cities were not an official league or political unit, but they were grouped together because of their language, culture, location, and political status...
and other Hellenized cities of Syria and Palestine used the Pompeian era
Pompeian era
The Pompeian Era was a calendar era used by Hellenistic cities in Roman Palestine, in particular the cities of the Decapolis. The calendar counted the years from the region's conquest by the Roman general Pompey in 63 BCE. Many of these cities had been self-governing poleis before the Jewish...
, counting dates from the Roman general Pompey
Pompey
Gnaeus Pompeius Magnus, also known as Pompey or Pompey the Great , was a military and political leader of the late Roman Republic...
's conquest of the region in 63 BC.
Maya
A different form of calendar was used to track longer periods of time, and for the inscription of calendar dates (i.e., identifying when one event occurred in relation to others). This form, known as the Long Count, is based upon the number of elapsed days since a mythological starting-point. According to the correlation between the Long Count and Western calendars accepted by the great majority of Maya researchers (known as the GMT correlation), this starting-point is equivalent to August 11, 3114 BC in the proleptic Gregorian calendar or 6 September in the Julian calendar (−3113 astronomical).Other dating systems
A great many local systems or eraEra
An era is a commonly used word for long period of time. When used in science, for example geology, eras denote clearly defined periods of time of arbitrary but well defined length, such as for example the Mesozoic era from 252 Ma–66 Ma, delimited by a start event and an end event. When used in...
s were also important, for example the year from the foundation of one particular city, the regnal year of the neighboring Persian emperor, and eventually even the year of the reigning Caliph
Caliph
The Caliph is the head of state in a Caliphate, and the title for the ruler of the Islamic Ummah, an Islamic community ruled by the Shari'ah. It is a transcribed version of the Arabic word which means "successor" or "representative"...
.
Late Antiquity and Middle Ages
Most of the traditional calendar eras in use today were introduced at the time of transition from Late AntiquityLate Antiquity
Late Antiquity is a periodization used by historians to describe the time of transition from Classical Antiquity to the Middle Ages, in both mainland Europe and the Mediterranean world. Precise boundaries for the period are a matter of debate, but noted historian of the period Peter Brown proposed...
to the Early Middle Ages
Early Middle Ages
The Early Middle Ages was the period of European history lasting from the 5th century to approximately 1000. The Early Middle Ages followed the decline of the Western Roman Empire and preceded the High Middle Ages...
, roughly between the 6th and 10th centuries.
Christian era
- The Etos Kosmou of the Byzantine CalendarByzantine calendarThe Byzantine calendar, also "Creation Era of Constantinople," or "Era of the World" was the calendar used by the Eastern Orthodox Church from c. 691 to 1728 in the Ecumenical Patriarchate. It was also the official calendar of the Byzantine Empire from 988 to 1453, and in Russia from c...
places Creation at the beginning of its year 1, namely 5509 BC. Its first known use occurred in the 7th century AD, although its precursors were developed about AD 400. The year 7509 of this era began in September 2000. - The Era of MartyrsEra of MartyrsThe Era of the Martyrs , also known as the Diocletian era , is a method of numbering years used by the Church of Alexandria beginning in the 4th century anno Domini and by the Coptic Orthodox Church of Alexandria from the 5th century to the present. Western Christians were aware of it but did not...
or Era of Diocletian is reckoned from the beginning of the reign of Roman Emperor DiocletianDiocletianDiocletian |latinized]] upon his accession to Diocletian . c. 22 December 244 – 3 December 311), was a Roman Emperor from 284 to 305....
; the first year of this era was 284/5. It was not the custom to use regnal years in Rome, but it was the custom in Roman Egypt, which the emperor ruled through a prefect (the king of Egypt). The year number changed on the first day of the Egyptian month Thoth (29 August three years out of four, 30 August the year before a Roman leap year.) Diocletian abolished the special status of Egypt, which thereafter followed the normal Roman calendar: consular years beginning on 1 January. This era was used in the Easter tables prepared in Alexandria long after the abdication of Diocletian, even though Diocletian was a notorious persecutor of Christians. The Era of Diocletian was retained by the Coptic ChurchCoptic calendarThe Coptic calendar, also called the Alexandrian calendar, is used by the Coptic Orthodox Church and still used in Egypt. This calendar is based on the ancient Egyptian calendar...
and used for general purposes, but by 643 the name had been changed to Era of the Martyrs. - The Incarnation EraEthiopian calendarThe Ethiopian calendar , also called the Ge'ez calendar, is the principal calendar used in Ethiopia and also serves as the liturgical calendar for Christians in Eritrea belonging to the Eritrean Orthodox Church, Eastern Catholic Church and Lutheran Evangelical Church of Eritrea...
is used by EthiopiaEthiopiaEthiopia , officially known as the Federal Democratic Republic of Ethiopia, is a country located in the Horn of Africa. It is the second-most populous nation in Africa, with over 82 million inhabitants, and the tenth-largest by area, occupying 1,100,000 km2...
. Its epoch is 29 August AD 8 in the Julian calendar. - The Armenian calendarArmenian calendarThe Armenian calendar is the traditional calendar of Armenia. It is a solar calendar based on the same system as the ancient Egyptian model, having an invariant 365-day year with no leap year rule...
has its era fixed at AD 552.
Dionysian "Common Era"
The era based on the IncarnationIncarnation (Christianity)
The Incarnation in traditional Christianity is the belief that Jesus Christ the second person of the Trinity, also known as God the Son or the Logos , "became flesh" by being conceived in the womb of a woman, the Virgin Mary, also known as the Theotokos .The Incarnation is a fundamental theological...
of Christ
Christ
Christ is the English term for the Greek meaning "the anointed one". It is a translation of the Hebrew , usually transliterated into English as Messiah or Mashiach...
was introduced by Dionysius Exiguus
Dionysius Exiguus
Dionysius Exiguus was a 6th-century monk born in Scythia Minor, modern Dobruja shared by Romania and Bulgaria. He was a member of the Scythian monks community concentrated in Tomis, the major city of Scythia Minor...
in 525 and is in continued use with various reforms and derivations. The distinction between the Incarnation being the conception or the Nativity of Jesus
Nativity of Jesus
The Nativity of Jesus, or simply The Nativity, refers to the accounts of the birth of Jesus in two of the Canonical gospels and in various apocryphal texts....
was not drawn until the late ninth century. The beginning of the numbered year varied from place to place; when, in 1600, Scotland adopted January 1 as the date the year number changes, this was already normal in continental Europe. England adopted this practice in 1752.
- A.D. (or AD) — for the LatinLatinLatin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
Anno DominiAnno Dominiand Before Christ are designations used to label or number years used with the Julian and Gregorian calendars....
, meaning "in the year of (our) Lord". This is the dominant or Western Christian Era; AD is used in the Gregorian calendar. Anno Salutis, meaning "in the year of salvation" is identical to this era. Originally intended to number years from the Incarnation of JesusJesusJesus of Nazareth , commonly referred to as Jesus Christ or simply as Jesus or Christ, is the central figure of Christianity...
, in fact the calculation was a few years off. Traditionally, years preceding AD 1 are numbered using the BC era, avoiding zero or negative numbers. AD was also used in the medieval Julian calendarJulian calendarThe Julian calendar began in 45 BC as a reform of the Roman calendar by Julius Caesar. It was chosen after consultation with the astronomer Sosigenes of Alexandria and was probably designed to approximate the tropical year .The Julian calendar has a regular year of 365 days divided into 12 months...
as well, but the first day of the year was either March 1, EasterEasterEaster is the central feast in the Christian liturgical year. According to the Canonical gospels, Jesus rose from the dead on the third day after his crucifixion. His resurrection is celebrated on Easter Day or Easter Sunday...
, March 25, September 1, or December 25, not January 1. To distinguish between the Julian and Gregorian calendars, O.S. and N.S. were often added to the date, especially during the 17th and 18th centuries, when both calendars were in common use. Old StyleOld Style and New Style datesOld Style and New Style are used in English language historical studies either to indicate that the start of the Julian year has been adjusted to start on 1 January even though documents written at the time use a different start of year ; or to indicate that a date conforms to the Julian...
(O.S.) was used for the Julian calendar and for years not beginning on January 1. New StyleOld Style and New Style datesOld Style and New Style are used in English language historical studies either to indicate that the start of the Julian year has been adjusted to start on 1 January even though documents written at the time use a different start of year ; or to indicate that a date conforms to the Julian...
(N.S.) was used for the Gregorian calendar and for Julian calendar years beginning on January 1. Many countries switched to using January 1 as the start of the numbered year when switching from the Julian calendar to the Gregorian calendar, but others switched earlier or later. - B.C. (or BC) — meaning "Before Christ". Used for years prior to AD 1, counting backwards so the year n BC is the year AD 1-n. Using these two calendar eras as historians use them means that there is no year 0Year zero"Year zero" does not exist in the widely used Gregorian calendar or in its predecessor, the Julian calendar. Under those systems, the year 1 BC is followed by AD 1...
or negative year numbers. - C.E. (or CE) — meaning "Common EraCommon EraCommon Era ,abbreviated as CE, is an alternative designation for the calendar era originally introduced by Dionysius Exiguus in the 6th century, traditionally identified with Anno Domini .Dates before the year 1 CE are indicated by the usage of BCE, short for Before the Common Era Common Era...
", numerically equivalent to the Anno Domini era. However, while AD precedes the year, CE follows the year (AD 1 = 1 CE). The first use of the Latin equivalent (vulgaris aera) discovered so far was in a 1615 book by Johannes KeplerJohannes KeplerJohannes Kepler was a German mathematician, astronomer and astrologer. A key figure in the 17th century scientific revolution, he is best known for his eponymous laws of planetary motion, codified by later astronomers, based on his works Astronomia nova, Harmonices Mundi, and Epitome of Copernican...
. - B.C.E. (or BCE) — meaning "Before the Common Era". Equivalent to B.C. (1 BC = 1 BCE.)
Dionysian-derived
- Astronomical year numberingAstronomical year numberingAstronomical year numbering is based on AD/CE year numbering, but follows normal decimal integer numbering more strictly. Thus, it has a year 0, the years before that are designated with negative numbers and the years after that are designated with positive numbers...
equates its year 0 with 1 BC, and counts negative years from 2 BC backward (−1 backward), so 100 BC is −99. - The Holocene calendarHolocene calendarThe Human Era, also known as the Holocene calendar or Holocene era , is a year numbering system that adds exactly 10,000 years to the currently world-dominant Anno Domini and Common Era system, placing its first year near the beginning of the Holocene epoch and the Neolithic revolution...
proposed by Cesare EmilianiCesare EmilianiCesare Emiliani was an Italian-American scientist, considered one of the greatest geologists and micropaleontologists of the 20th century and the founder of paleoceanography, developing the timescale of marine isotope stages, which despite modifications remains in very wide use today.He...
placed its year 1 at 10,000 BC. - Anno LucisAnno LucisAnno Lucis is a dating system used in Freemasonry that is similar to, but different from Anno Mundi.-Description:In their ceremonial or commemorative proceedings, Freemasons add 4,000 years to the current Anno Domini calendar year and append Anno Lucis to the Gregorian calendar year .This...
of FreemasonryFreemasonryFreemasonry is a fraternal organisation that arose from obscure origins in the late 16th to early 17th century. Freemasonry now exists in various forms all over the world, with a membership estimated at around six million, including approximately 150,000 under the jurisdictions of the Grand Lodge...
adds 4000 years to the AD year.
Islamic
- A.H. (or AH) — for the Latinized Anno Hegirae, meaning "in the year of the HijraHijra (Islam)The Hijra is the migration or journey of the Islamic prophet Muhammad and his followers from Mecca to Medina in 622 CE. Alternate spellings of this Arabic word are Hijrah, Hijrat or Hegira, the latter following the spelling rules of Latin.- Hijra of Muhammad :In September 622, warned of a plot to...
", Prophet MuhammadMuhammadMuhammad |ligature]] at U+FDF4 ;Arabic pronunciation varies regionally; the first vowel ranges from ~~; the second and the last vowel: ~~~. There are dialects which have no stress. In Egypt, it is pronounced not in religious contexts...
's migration from Mecca to Medina in September 622, which occurred in its first year, used in the Islamic calendarIslamic calendarThe Hijri calendar , also known as the Muslim calendar or Islamic calendar , is a lunar calendar consisting of 12 lunar months in a year of 354 or 355 days. It is used to date events in many Muslim countries , and used by Muslims everywhere to determine the proper day on which to celebrate Islamic...
. Since the Islamic calendar is a purely lunar calendarLunar calendarA lunar calendar is a calendar that is based on cycles of the lunar phase. A common purely lunar calendar is the Islamic calendar or Hijri calendar. A feature of the Islamic calendar is that a year is always 12 months, so the months are not linked with the seasons and drift each solar year by 11 to...
of about 354 days, its year count increases faster than that of solarSolar calendarA solar calendar is a calendar whose dates indicate the position of the earth on its revolution around the sun .-Tropical solar calendars:...
and lunisolar calendarLunisolar calendarA lunisolar calendar is a calendar in many cultures whose date indicates both the moon phase and the time of the solar year. If the solar year is defined as a tropical year then a lunisolar calendar will give an indication of the season; if it is taken as a sidereal year then the calendar will...
s. - A.H.S. (or AHS) is used by the Iranian calendarIranian calendarThe Iranian calendars or sometimes called Persian calendars are a succession of calendars invented or used for over two millennia in Greater Iran...
to denote the number of solar years since the Hijra. The year beginning at the vernal equinox equals the number of the Gregorian year beginning at the preceding January 1 minus 621.
Hindu
- Hindu calendarHindu calendarThe hindu calendar used in ancient times has undergone many changes in the process of regionalization, and today there are several regional Indian calendars, as well as an Indian national calendar. Nepali calendar, Bengali calendar, Malayalam calendar, Tamil calendar, Telugu calendar, Kannada...
, counting from the start of the Kali YugaKali YugaKali Yuga is the last of the four stages that the world goes through as part of the cycle of yugas described in the Indian scriptures. The other ages are Satya Yuga, Treta Yuga and Dvapara Yuga...
, with its epoch on February 18, 3102 BC Julian (January 23, 3102 BC Gregorian), based on Aryabhata (6th century). - Vikrama Samvat, 56-57 BC, introduced about the 12th century.
- S.E. or (SE) — for the Saka EraSakaThe Saka were a Scythian tribe or group of tribes....
, used in some Hindu calendarHindu calendarThe hindu calendar used in ancient times has undergone many changes in the process of regionalization, and today there are several regional Indian calendars, as well as an Indian national calendar. Nepali calendar, Bengali calendar, Malayalam calendar, Tamil calendar, Telugu calendar, Kannada...
s and in the Indian national calendarIndian national calendarThe Indian national calendar is the official civil calendar in use in India. It is used, alongside the Gregorian calendar, by The Gazette of India, news broadcasts by All India Radio, and calendars and communications issued by the Government of India.The term may also ambiguously refer to the...
, with an epoch near the vernal equinox of year 78 (its year 0); its usage spread to Southeast Asia before year 1000. This era is also used (together with the Gregorian calendar) in the Indian national calendar, the official civil calendar used in communiques issued by the Government of India.
Zoroastrian
- The Zoroastrian calendarZoroastrian calendarThis article treats of the reckoning of days, months and years in the calendar used by adherents of the Zoroastrian faith. Zoroastrian religious festivals are discussed elsewhere, but have a fixed relationship to Nawruz, the New Year festival, whose timing is discussed below...
used regnal years since the reform by Ardeshir I, but after the fall of the Sassanid empireSassanid EmpireThe Sassanid Empire , known to its inhabitants as Ērānshahr and Ērān in Middle Persian and resulting in the New Persian terms Iranshahr and Iran , was the last pre-Islamic Persian Empire, ruled by the Sasanian Dynasty from 224 to 651...
, the ascension of the last Sassanid ruler, Yazdegerd III of Persia, crowned 16 June 632, continued to be used as the reference year, abbreviated Y.Z. or "Yazdegerd era".
Jewish
- A.M.Anno Mundi' , abbreviated as AM or A.M., refers to a Calendar era based on the Biblical creation of the world. Numerous efforts have been made to determine the Biblical date of Creation, yielding varying results. Besides differences in interpretation, which version of the Bible is being referenced also...
(or AM) — for the Latin Anno MundiAnno Mundi' , abbreviated as AM or A.M., refers to a Calendar era based on the Biblical creation of the world. Numerous efforts have been made to determine the Biblical date of Creation, yielding varying results. Besides differences in interpretation, which version of the Bible is being referenced also...
, meaning "in the year of the world", has its epoch in the year 3761 BC. This was first used to number the years of the modern Hebrew calendarHebrew calendarThe Hebrew calendar , or Jewish calendar, is a lunisolar calendar used today predominantly for Jewish religious observances. It determines the dates for Jewish holidays and the appropriate public reading of Torah portions, yahrzeits , and daily Psalm reading, among many ceremonial uses...
in 1178 by MaimonidesMaimonidesMoses ben-Maimon, called Maimonides and also known as Mūsā ibn Maymūn in Arabic, or Rambam , was a preeminent medieval Jewish philosopher and one of the greatest Torah scholars and physicians of the Middle Ages...
. Precursors with epochs one or two years later were used since the 3rd century, all based on the Seder Olam Rabba of the 2nd century. The year beginning in the northern autumn of 2000 was 5761 AM).
Political
- The Republican Era of the French Republican CalendarFrench Republican CalendarThe French Republican Calendar or French Revolutionary Calendar was a calendar created and implemented during the French Revolution, and used by the French government for about 12 years from late 1793 to 1805, and for 18 days by the Paris Commune in 1871...
was dated from 22 September 1792, the day of the proclamation of the French First RepublicFrench First RepublicThe French First Republic was founded on 22 September 1792, by the newly established National Convention. The First Republic lasted until the declaration of the First French Empire in 1804 under Napoleon I...
. It was used in Revolutionary France from October 24, 1793 (on the Gregorian calendar) to December 31, 1805. - The Positivist calendarPositivist calendarThe positivist calendar was a calendar reform proposal by Auguste Comte in 1849. After revising the earlier work of Marco Mastrofini, Comte's proposed calendar was a solar calendar which had 13 months of 28 days, and an additional festival day commemorating the dead, totalling 365 days.This extra...
of 1844 takes 1789 as its epoch. - The Republican eraMinguo calendarThe Republic of China calendar is the method of numbering years currently used in the Republic of China . It was used in mainland China from 1912 until the founding of the People's Republic of China in 1949....
is used by the Republic of ChinaRepublic of ChinaThe Republic of China , commonly known as Taiwan , is a unitary sovereign state located in East Asia. Originally based in mainland China, the Republic of China currently governs the island of Taiwan , which forms over 99% of its current territory, as well as Penghu, Kinmen, Matsu and other minor...
(Taiwan) since 1929, assigning year one to 1912, the first year of the republic. Coincidentally, this is the same as the Juche era used in North KoreaNorth KoreaThe Democratic People’s Republic of Korea , , is a country in East Asia, occupying the northern half of the Korean Peninsula. Its capital and largest city is Pyongyang. The Korean Demilitarized Zone serves as the buffer zone between North Korea and South Korea...
, the year of the birth of its founder Kim Il-SungKim Il-sungKim Il-sung was a Korean communist politician who led the Democratic People's Republic of Korea from its founding in 1948 until his death in 1994. He held the posts of Prime Minister from 1948 to 1972 and President from 1972 to his death...
. - The Italian FascistsFascismFascism is a radical authoritarian nationalist political ideology. Fascists seek to rejuvenate their nation based on commitment to the national community as an organic entity, in which individuals are bound together in national identity by suprapersonal connections of ancestry, culture, and blood...
used Roman numeralsRoman numeralsThe numeral system of ancient Rome, or Roman numerals, uses combinations of letters from the Latin alphabet to signify values. The numbers 1 to 10 can be expressed in Roman numerals as:...
to denote the number of years since the establishment of the Fascist government in 1922. Therefore, 1934, for example, was Year XII. This era was abolished with the fall of fascism in Italy on July 25, 1943, but restored in the northern part of the country during the Italian Social RepublicItalian Social RepublicThe Italian Social Republic was a puppet state of Nazi Germany led by the "Duce of the Nation" and "Minister of Foreign Affairs" Benito Mussolini and his Republican Fascist Party. The RSI exercised nominal sovereignty in northern Italy but was largely dependent on the Wehrmacht to maintain control...
. - China traditionally reckoned by the regnal year of its emperors, see Chinese era nameChinese era nameA Chinese era name is the regnal year, reign period, or regnal title used when traditionally numbering years in an emperor's reign and naming certain Chinese rulers . Some emperors have several era names, one after another, where each beginning of a new era resets the numbering of the year back...
. Most Chinese do not assign numbers to the years of the Chinese calendarChinese calendarThe Chinese calendar is a lunisolar calendar, incorporating elements of a lunar calendar with those of a solar calendar. It is not exclusive to China, but followed by many other Asian cultures as well...
, but the few who do, like expatriate Chinese, use a continuous count of years from the reign of the legendary Yellow EmperorYellow EmperorThe Yellow Emperor or Huangdi1 is a legendary Chinese sovereign and culture hero, included among the Three Sovereigns and Five Emperors. Tradition holds that he reigned from 2697–2597 or 2696–2598 BC...
, using 2698 BC as year 1. Western writers begin this count at either 2637 BC or 2697 BC (see Chinese calendar). Thus, the Chinese years 4637, 4697, or 4698 began in early 2000. - In Korea, from 1952 until 1961 years were numbered via Dangi years, where 2333 BC was regarded as the first such year.
- The Assyrian calendarAssyrian calendarThe Assyrian calendar is a lunar-based calendar that begins in the year 4750 BC, inspired by an estimate of the date of the first temple at Ashur, notably based on a series of articles published in the Assyrian magazine Gilgamesh, edited by the brothers Addi and Jean Alkhas and Nimrod Simono. The...
, introduced in the 1950s, has its era fixed at 4750 BC. - The Japanese calendarJapanese calendarOn January 1, 1873, Japan adopted the Gregorian calendar. Before 1873, the Chinese style lunisolar calendar had been in use since 7th century. Japanese eras are still in use.-System:...
dates from the accession of the current Emperor of JapanEmperor of JapanThe Emperor of Japan is, according to the 1947 Constitution of Japan, "the symbol of the state and of the unity of the people." He is a ceremonial figurehead under a form of constitutional monarchy and is head of the Japanese Imperial Family with functions as head of state. He is also the highest...
. The current emperor took the throne in early 1989, which became Heisei 1, which was until then Shōwa 64 (for its first seven days).
Religious
- B.E.Buddhist calendarThe Buddhist calendar is used on mainland Southeast Asia in the countries of Thailand, Cambodia, Laos, Burma and Sri Lanka in several related forms. It is a lunisolar calendar having months that are alternately 29 and 30 days, with an intercalated day and a 30-day month added at regular intervals...
— for the Buddhist EraBuddhist calendarThe Buddhist calendar is used on mainland Southeast Asia in the countries of Thailand, Cambodia, Laos, Burma and Sri Lanka in several related forms. It is a lunisolar calendar having months that are alternately 29 and 30 days, with an intercalated day and a 30-day month added at regular intervals...
, introduced by VajiravudhVajiravudhPhra Bat Somdet Phra Poramentharamaha Vajiravudh Phra Mongkut Klao Chao Yu Hua , or Phra Bat Somdet Phra Ramathibodi Si Sintharamaha Vajiravudh Phra Mongkut Klao Chao Yu Hua , or Rama VI was the sixth monarch of Siam under the House of Chakri, ruling from 1910 until his death...
in 1912, which has an epochEpoch (reference date)In the fields of chronology and periodization, an epoch is an instance in time chosen as the origin of a particular era. The "epoch" then serves as a reference point from which time is measured...
(origin) of 544 BC. This year is called year 1 in Sri LankaSri LankaSri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
and Burma, but year 0 in ThailandThailandThailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...
, LaosLaosLaos Lao: ສາທາລະນະລັດ ປະຊາທິປະໄຕ ປະຊາຊົນລາວ Sathalanalat Paxathipatai Paxaxon Lao, officially the Lao People's Democratic Republic, is a landlocked country in Southeast Asia, bordered by Burma and China to the northwest, Vietnam to the east, Cambodia to the south and Thailand to the west...
and CambodiaCambodiaCambodia , officially known as the Kingdom of Cambodia, is a country located in the southern portion of the Indochina Peninsula in Southeast Asia...
. Thus the year 2500 B.E. occurred in 1956 in the former countries, but in 1957 in the latter. In Thailand in 1888 King ChulalongkornChulalongkornPhra Bat Somdet Phra Poramintharamaha Chulalongkorn Phra Chunla Chom Klao Chao Yu Hua , or Rama V was the fifth monarch of Siam under the House of Chakri. He was known to the Siamese of his time as Phra Phuttha Chao Luang . He is considered one of the greatest kings of Siam...
decreed a National Thai Era, dating from the founding of BangkokBangkokBangkok is the capital and largest urban area city in Thailand. It is known in Thai as Krung Thep Maha Nakhon or simply Krung Thep , meaning "city of angels." The full name of Bangkok is Krung Thep Mahanakhon Amon Rattanakosin Mahintharayutthaya Mahadilok Phop Noppharat Ratchathani Burirom...
on April 6, 1782. In 1912 New Year's Day was shifted to April 1. In 1941 Prime Minister PhibunsongkhramPlaek PibulsonggramField Marshal Plaek Pibunsongkhram , often known as Phibun Songkhram or simply Phibun in English, was Prime Minister and virtual military dictator of Thailand from 1938 to 1944 and 1948 to 1957.- Early years :...
decided to count the years since 543 BC. This is the Thai solar calendarThai solar calendarThe Thai solar calendar, Suriyakati was adopted by King Chulalongkorn in AD 1888 as the Siamese version of the Gregorian calendar. It is the legal calendar in Thailand, though Thai lunar calendar dates continue in use. Years are now counted in the Buddhist Era that is 543 years greater than...
using the Thai Buddhist Era aligned to the western solar calendar. - B.E. — The Bahá'í calendarBahá'í calendarThe Bahá'í calendar, also called the Badí‘ calendar , used by the Bahá'í Faith, is a solar calendar with regular years of 365 days, and leap years of 366 days. Years are composed of 19 months of 19 days each, plus an extra period of "Intercalary Days"...
dates from the year of the declaration of the BábBábSiyyid `Alí Muḥammad Shírází was the founder of Bábism, and one of three central figures of the Bahá'í Faith. He was a merchant from Shíráz, Persia, who at the age of twenty-four claimed to be the promised Qá'im . After his declaration he took the title of Báb meaning "Gate"...
. Years are counted in the Bahá'í Era (BE), which starts its year 1 from March 21, 1844.
Practical
- B.P.Before PresentBefore Present years is a time scale used in archaeology, geology, and other scientific disciplines to specify when events in the past occurred. Because the "present" time changes, standard practice is to use AD 1950 as the origin of the age scale, reflecting the fact that radiocarbon...
— for Before PresentBefore PresentBefore Present years is a time scale used in archaeology, geology, and other scientific disciplines to specify when events in the past occurred. Because the "present" time changes, standard practice is to use AD 1950 as the origin of the age scale, reflecting the fact that radiocarbon...
, specifically, the number of radiocarbonRadiocarbon datingRadiocarbon dating is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Raw, i.e. uncalibrated, radiocarbon ages are usually reported in radiocarbon years "Before Present" ,...
years before 1950. - The Unix epoch is set at midnight UTC of January 1, 1970, even though there are problems with Unix's implementation of UTC which are detailed at Unix epoch.
- The Julian day number counts days, not years, and has its era fixed at noon January 1, 4713 BC in the proleptic Julian calendarProleptic Julian calendarThe proleptic Julian calendar is produced by extending the Julian calendar to dates preceding AD 4 when its quadrennial leap year stabilized. The leap years actually observed between its official implementation in 45 BC and AD 4 were erratic, see the Julian calendar article for details.A calendar...
. This equals November 24, 4714 BC in the proleptic Gregorian calendarProleptic Gregorian calendarThe proleptic Gregorian calendar is produced by extending the Gregorian calendar backward to dates preceding its official introduction in 1582.-Usage:...
. From noon of this day to noon of the next day was day 0. Multiples of 7 are Mondays. Negative values can also be used. Apart from the choice of the zero point and name, this Julian day and Julian date are not related to the Julian calendarJulian calendarThe Julian calendar began in 45 BC as a reform of the Roman calendar by Julius Caesar. It was chosen after consultation with the astronomer Sosigenes of Alexandria and was probably designed to approximate the tropical year .The Julian calendar has a regular year of 365 days divided into 12 months...
. It does not count years, so, strictly speaking, it has no era, but it does have an epochEpoch (reference date)In the fields of chronology and periodization, an epoch is an instance in time chosen as the origin of a particular era. The "epoch" then serves as a reference point from which time is measured...
. Today (noon-to-noon UTC) the value is .