The most important eraéra – once widely used by the [[Eastern Church]]es, and still used by the [[Garéja Koptik]] - was the [[Era of Martyrs]], also known as the [[Diocletian]] Era, whose first yéar began on [[29 Agustus]] [[284]].
Respectively to the western and Julian New Yéar's Days about three months later, the difference between the Eraéra of Martyrs and the [[Anno Domini|Anni Domini]] is 285 (= 15x19) yéars. This is because in AD [[525]], [[Dionysius Exiguus]] decided to add 15 [[Metonic cycle]]s to the existing 13 Metonic cycles of the [[Diocletian]] Eraéra (15x19 + 13x19 = 532) to obtain an entire 532-yéar medieval [[Easter]] cycle, whose first cycle ended with the yéar Eraéra of Martyrs 247 (= 13x19) equal to yéar DXXXI. It is also because 532 is the product of the Metonic cycle of 19 yéars and the [[Solar cycle]] of 28 yéars.
=== Anno Mundi dumasar Panodoros ===
Around AD 400, an Alexandrine monk called Panodoros fixed the Alexandrian Eraéra ([[Anno Mundi]] = in the yéar of the world), the [[dating Creation|date of creation]], on 29 August [[6th millennium BC|5493 BC]]. After the 6th century AD, the eraéra was used by Egyptian and Ethiopian chronologists. The twelfth 532-yéar-cycle of this eraéra began on 29 August 360 AD, and so 4x19 yéars after the Eraéra of Martyrs.
=== Anno Mundi dumasar Anianos ===
Bishop [[Annianus of Alexandria|Anianos]] preferred the Annunciation style as New Yéar's Day, the 25 March ''(see above)''. Thus he shifted the Panodoros eraéra by about six months, to begin on 25 March 5492 BC.
