How the AD and BC was decided? When and how the years are calculated especially the BC?

Answer 1

from the below source

In about AD 523, the papal chancellor, Bonifatius, asked a monk by the name of Dionysius Exiguus to devise a way to implement the rules from the Nicean council (the so-called ``Alexandrine Rules'') for general use.

Dionysius Exiguus (in English known as Denis the Little) was a monk from Scythia, he was a canon in the Roman curia, and his assignment was to prepare calculations of the dates of Easter. At that time it was customary to count years since the reign of emperor Diocletian; but in his calculations Dionysius chose to number the years since the birth of Christ, rather than honour the persecutor Diocletian.

Dionysius (wrongly) fixed Jesus' birth with respect to Diocletian's reign in such a manner that it falls on 25 December 753 AUC (ab urbe condita, i.e. since the founding of Rome), thus making the current era start with AD 1 on 1 January 754 AUC.

How Dionysius established the year of Christ's birth is not known (see section 2.14.1 for a couple of theories). Jesus was born under the reign of king Herod the Great, who died in 750 AUC, which means that Jesus could have been born no later than that year. Dionysius' calculations were disputed at a very early stage.

When people started dating years before 754 AUC using the term ``Before Christ'', they let the year 1 BC immediately precede AD 1 with no intervening year zero.

Note, however, that astronomers frequently use another way of numbering the years BC. Instead of 1 BC they use 0, instead of 2 BC they use -1, instead of 3 BC they use -2, etc.

Answer 2

Our calendar system is based on the year that Jesus Christ was born. At least that was the intention. The actual numbering of the years from the birth of Christ was developed by a monk named Dionysius Exiguus (born in Scythia Minor) in Rome in
AD 525. So some calculations needed to be made to determine how many years ago Jesus was born. Some people think he may have erred by a few years.

Here is a link that discusses it.

http://en.wikipedia.org/wiki/Anno_Domini

BC means Before Christ. And AD stands for the Latin phrase "Anno Domini", which means "In the Year of Our Lord." So BC is the number of years before Jesus Christ was born and AD is the number of years after He was born.

Answer 3

AD and BC were instituted to show the birth of the supposed saviour, ot at least at close to that date as possible. BC (Before Christ) basicall counts down to the magical date, while AD (Ano Domini) counts upwards for jesus's birth. It comes from a time when britain and other countries were still under the control of the pope, and the papal date system forced this calander. The jews, who don't believe in christ, still use another calender, showing a different year.

Answer 4

BC= before christ
AD= after christ

Answer 5

anno domini basically means in the year of our lord - and bc was of course Before Christ - just imagine all those confused egyptians and pagans all asking - what are we counting down to?

Answer 6

Don't forget b.c.e.

http://en.wikipedia.org/wiki/Anno_Domini

Answer 7

BC before Christ, get it.

Answer 8

http://en.wikipedia.org/wiki/Anno_Domini

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