add links & source
Derived from the [[Septuagint]], it placed the date of creation at 5,509 years before the [[Incarnation]], and was characterized by a certain tendency which had already been a tradition amongst Hebrews and Jews to number the years ''' ''from the beginning of the world'' ''' - '''‘[[w:Etos Kosmou|Etos Kosmou / Apo Kataboles Kosmou]]’''' (Greek: ''Έτος Κόσμου,'' ''Από Κτίσεως Κόσμου''), or '''‘[[w:Anno Mundi|Annus Mundi / Ab Origine Mundi]]’''' '''AM''' (Latin).
We do not know who invented this era and when, however it appears for the first time in the treatise of a certain “[[monk]] and [[Presbyter|priest]]”, Georgios (AD 638-39), who mentions all the main variants of the ''"World Era"'' (''Ére Mondiale'') in his work.<ref>Fr. Diekamp, ''“Der Mönch und Presbyter Georgios, ein unbekannter Schriftsteller des 7. Jahrhunderts,”'' BZ 9 (1900) 14–51.</ref><ref>Pavel Kuzenkov (Moscow). ''[http://www.wra1th.plus.com/byzcong/comms/Kuzenkov_paper.pdf How old is the World? The Byzantine era κατα Ρωμαίους and its rivals]''. 21st International Congress of Byzantine Studies, London 2006. p.3.</ref>. Georgios makes it clear that the main advantage of the Byzantine era is the common starting point of the astronomical [[w:
Lunisolar calendar|lunar and solar cycles]], and of the cycle of [[Indiction|indictions]], the usual dating system in Byzantium since the sixth century. He also already regards it as the most convenient for the [[Pascha|Easter]] computus. 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 [[Nativity|birth of Christ]] or the [[Crucifixion]].<ref>Prof. Dr. [http://aha.missouri.edu/people/rautman.html Marcus Louis Rautman]. ''"Time."'' In [http://books.google.ca/books?id=hs3iEyVRHKsC&printsec=frontcover&dq=Daily+Life+in+the+Byzantine+Empire ''Daily Life in the Byzantine Empire'']. Greenwood Publishing Group, 2006. pp.7</ref>
This date underwent minor revisions before being finalized in the seventh century A.D., although its precursors were developed circa AD 412 (see [[Byzantine_Creation_Era#Alexandrian_Era|''Alexandrian Era'']]). By the second half of the 7th century the ''Creation Era'' was known in the far West of Europe, in Britain.<ref>Pavel Kuzenkov (Moscow). ''[http://www.wra1th.plus.com/byzcong/comms/Kuzenkov_paper.pdf How old is the World? The Byzantine era κατα Ρωμαίους and its rivals]''. 21st International Congress of Byzantine Studies, London 2006. p.4. (PL XC, 598, 877 (Pseudo‐Beda)).</ref> By the late tenth century around AD 988<ref>i.e. From the reign of Emperor Basil II (Βασίλειος Β' ο Βουλγαροκτόνο), (976-1025), who officially used this calendar. It was during this time (ca. 988) that the [[w:Coptic calendar|''Alexandrian System'']] was officially superceded in Byzantium by the ''Byzantine Creation Era''.</ref> a unified system was widely recognized across the Eastern Roman world.
To this day, traditional Orthodox Christians will use the Byzantine calculation of the [[w:Etos Kosmou|Etos Kosmou]] in conjunction with the [[w:Anno Domini|Anno Domini]] (AD) year. Both dates appear on Orthodox cornerstones, ecclesiastical calendars and formal documents. The ecclesiastical new year is still observed on [[September 1]] (or on the Gregorian Calendar's [[September 14]] for those churches which follow the [[Julian Calendar]]). September 2008 marked the beginning of the year 7517 of this era.
* [[Gaussian Formulae]]
* [[w:Anno Mundi|Anno Mundi]].
* [[w:Dating Creation|Dating Creation]].
* [[w:Etos Kosmou|Etos Kosmou]].
* [[w:Ex nihilo|Ex nihilo]]
* [[w:Lunisolar calendar|Lunisolar calendar]].
* [[w:Young Earth creationism|Young Earth creationism]]
:'''Other Judeo-Christian Eras'''
:* [[w:Coptic calendar|Coptic Calendar]]. (Note: the '''"''Alexandrian Era''"''' (March 25, 5493 BC), is totally distinct from the Coptic "Alexandrian Calendar", which is derived from the ancient [[w:Egyptian calendar|Egyptian Calendar]], and based on the ''' ''Era of the Martyrs'' ''' ([[August 29]], 284)).
* E.G. Richards. ''Mapping Time: The Calendar and its History''. Oxford University Press, 1998. (''Good overall general review of the history and astronomical basis of the principal calendars that have been used throughout history all around the world'').
* Elias J. Bickerman. ''Chronology of the Ancient World''. 2nd edition. Cornell University Press. 1980.
* Fr. [[Seraphim Rose]]. ''GENESIS, CREATION and EARLY MAN: The Orthodox Christian Vision''. St. Herman of Alaska Brotherhood, Platina, CA, 2000.
* Fr. Stanley S. Harakas. ''The Orthodox Church: 455 Questions and Answers''. Light & Life Publishing, Minneapolis, 1988.
* George Ogg. ''Hippolytus and the Introduction of the Christian Era.'' in '''Vigiliae Christianae''', Vol.16, No.1 (Mar., 1962), pp.2-18.
* Howlett, J. ''[http://www.newadvent.org/cathen/03731a.htm Biblical Chronology]''. In '''The Catholic Encyclopedia (New Advent)'''. New York: Robert Appleton Company, 1908.
* V. Grumel. ''La Chronologie''. Presses Universitaires France, Paris. 1958.
* Yiannis E. Meimaris. ''Chronological Systems in Roman-Byzantine Palestine and Arabia''. Athens, 1992.