“Our Western dating system–BC (Before Christ) and AD (Anno Domini–Year of Our Lord)–was conceived in the sixth century by a Romanian monk called Dionysius Exiguus, and came into widespread scholarly use after its adoption by the Anglo-Saxon historian the Venerable Bede. Prior to that, European historians dated years according to the Roman consul who held office in a given year.
Working in Rome, Dionysius declared that the current year was 525 AD, based on the birth of Christ taking place in the year 1 (there being not Western concept at the time of zero). Gospel historians later decided that Jesus was actually born a few years earlier, between 6 and 4 BC. Dionysius, it seems, may have wanted to disprove the idea that the end of the world would take place 500 years after the Birth of Jesus. That would have made it 6000 years after the creation, which was believed to have taken place 5500 years before Christ. Dionysius himself estimated, based on cosmological readings, that the end of the world would take place in 2000.
The CE/BCE (Common Era) designations, increasingly used to secularize history, are widely regarded as modern, politically correct innovations but were in fact introduced by Jewish historians in the mid-nineteenth century. But for those who might want an alternative, there are plenty of other dating systems. The Jews start their calendar in 3761 BC; the Mayans, in 3114 BC; the Chinese, with the start of the Yellow Emperor’s reign in 2696 BC; the Japanese in 680 BC; the Muslims, with the emigration of the Prophet Muhammad to Medina from Mecca in 622 AD; the Copts, with the Year of the Martyrs in 284 AD, while the Ethiopian Church starts the clock back in 5493 BC.”
Excerpted from: Rogerson, Barnaby. Rogerson’s Book of Numbers: The Culture of Numbers–from 1,001 Nights to the Seven Wonders of the World. New York: Picador, 2013.