The Byzantine calendar, also called "Creation Era of Constantinople" or "Era of the World" (Ancient Greek: Ἔτη Γενέσεως Κόσμου κατὰ Ῥωμαίους, also Ἔτος Κτίσεως Κόσμου or Ἔτος Κόσμου, abbreviated as ε.Κ.; literal translation of ancient Greek "Roman year since the creation of the universe"), 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, of Kievan Rus' and Russia from c. 988 to 1700,[note 1] as well as being used in other areas of the Byzantine commonwealth such as in Serbia. Since Byzantine is a historiographical term, the original name uses the adjective "Roman" as it was what the Eastern Roman Empire continued calling itself.[note 2]
The calendar was based on the Julian calendar, except that the year started on 1 September and the year number used an Anno Mundiepoch derived from the Septuagint version of the Bible. It placed the date of creation at 5509 years before the incarnation, and was characterized by a certain tendency which had already been a tradition among Jews and early Christians to number the years from the calculated foundation of the world (Latin: Annus Mundi or Ab Origine Mundi— "AM").[note 3] Its Year One, marking the supposed date of creation, was September 1, 5509 BC, to August 31, 5508 BC. This would make the current year (AD 2020) 7528.
The first appearance of the term is in the treatise of a monk and priest, Georgios (AD 638–39), who mentions all the main variants of the "World Era" in his work. Georgios argues that the main advantage of the World era is the common starting point of the astronomical lunar and solar cycles, and of the cycle of indictions, the usual dating system in Byzantium since the 6th century. He also regarded it as the most convenient for the Eastercomputus. Complex calculations of the 19-year lunar and 28-year solar cycles within this world era allowed scholars to discover the cosmic significance of certain historical dates, such as the birth or the crucifixion of Jesus.
This date underwent minor revisions before being finalized in the mid-7th century, although its precursors were developed c. AD 412. By the second half of the 7th century, the Creation Era was known in Western Europe, at least in Great Britain.[note 4] By the late 10th century (around AD 988), when the era appears in use on official government records, a unified system was widely recognized across the Eastern Roman world.
The era was ultimately calculated as starting on September 1, and Jesus was thought to have been born in the year 5509 since the creation of the world.[note 5] Historical time was thus calculated from the creation, and not from Christ's birth as it was in the west after the Anno Domini system adopted between the 6th and 9th centuries. The eastern Church avoided the use of the Anno Domini system of Dionysius Exiguus, since the date of Christ's birth was debated in Constantinople as late as the 14th century.
its era was based on the year of creation, reckoned September 1, 5509 BC, to August 31, 5508 BC, rather than the foundation of Rome; years were also reckoned by their place in the indiction and not by the years' consuls.
The leap day of the Byzantine calendar was obtained in an identical manner to the bissextile day of the original Roman version of the Julian calendar, by doubling the sixth day before the calends of March, i.e., by doubling 24 February.
The Byzantine World Era was gradually replaced in the Orthodox Church by the Christian Era (Anno Domini), which was utilized initially by Patriarch Theophanes I Karykes in 1597, afterwards by Patriarch Cyril Lucaris in 1626, and then formally established by the Church in 1728.[note 9] Meanwhile, as Russia received Orthodox Christianity from Byzantium, she inherited the Orthodox calendar based on the Byzantine Era (translated into Slavonic). After the collapse of the Byzantine Empire in 1453, the era continued to be used by Russia, which witnessed millennialist movements in Moscow in AD 1492 (7000 AM).[note 10] It was only in AD 1700 that the Byzantine calendar in Russia was changed to the Julian calendar by Peter the Great. It still forms the basis of traditional Orthodox calendars up to today. September AD 2000 began the year 7509 AM.[note 11]
God as architect of the world. (Frontispiece of Bible moralisée, c. 1220–1230).
The earliest extant Christian writings on the age of the world according to the biblical chronology are by Theophilus (AD 115–181) in his apologetic work To Autolycus, and by Julius Africanus (AD 200–245) in his Five Books of Chronology. Both of these early Christian writers, following the Septuagint version of the Old Testament, determined the age of the world to have been about 5,530 years at the birth of Christ.
Ben Zion Wacholder points out that the writings of the Church Fathers on this subject are of vital significance (even though he disagrees with their chronological system based on the authenticity of the Septuagint, as compared to that of the Masoretic Text), in that through the Christian chronographers a window to the earlier Hellenistic biblical chronographers[note 12] is preserved:
The Alexandrian Era (Greek: Κόσμου ἔτη κατ’ Ἀλεξανδρεῖς, Kósmou étē kat'Alexandreîs) developed in AD 412, was the precursor to the Byzantine Era. After the initial attempts by Hippolytus, Clement of Alexandria and others,[note 13] the Alexandrian computation of the date of creation was worked out to be 25 March 5493 BC.
The Alexandrine monk Panodorus reckoned 5904 years from Adam to the year AD 412. His years began with August 29, corresponding to the First of Thoth, the Egyptian new year.Annianos of Alexandria however, preferred the Annunciation style[clarification needed] as New Year's Day, 25 March, and shifted the Panodorus era by about six months, to begin on 25 March. This created the Alexandrian Era, whose first day was the first day of the proleptic[note 14] Alexandrian civil year in progress, 29 August 5493 BC, with the ecclesiastical year beginning on 25 March 5493 BC.
This system presents in a masterly sort of way the mystical coincidence of the three main dates of the world's history: the beginning of Creation, the incarnation, and the Resurrection of Jesus Christ. All these events happened, according to the Alexandrian chronology, on 25 March; furthermore, the first two events were separated by the period of exactly 5500 years; the first and the third one occurred on Sunday — the sacred day of the beginning of the Creation and its renovation through Christ.
Dionysius of Alexandria had earlier emphatically quoted mystical justifications for the choice of March 25 as the start of the year:
March 25 was considered to be the anniversary of Creation itself. It was the first day of the year in the medieval Julian calendar and the nominal vernal equinox (it had been the actual equinox at the time when the Julian calendar was originally designed). Considering that Christ was conceived at that date turned March 25 into the Feast of the Annunciation which had to be followed, nine months later, by the celebration of the birth of Christ, Christmas, on December 25.
A new variant of the World Era was suggested in the Chronicon Paschale, a valuable Byzantine universal chronicle of the world, composed about the year 630 AD by some representative of the Antiochian scholarly tradition. It had for its basis a chronological list of events extending from the creation of Adam to the year AD 627. The chronology of the writer is based on the figures of the Bible and begins with 21 March, 5507.
For its influence on Greek Christian chronology, and also because of its wide scope, the Chronicon Paschale takes its place beside Eusebius, and the chronicle of the monk Georgius Syncellus which was so important in the Middle Ages; but in respect of form it is inferior to these works.
By the late 10th century, the Byzantine Era, which had become fixed at September 1 5509 BC since at least the mid-7th century (differing by 16 years from the Alexandrian date, and 2 years from the Chronicon Paschale), had become the widely accepted calendar of choice par excellence for Chalcedonian Orthodoxy.