Today the international standard is to designate years based on a traditional reckoning of the year Jesus was born — the “A. D." stands for , Latin for “in the year of the lord,” and refers specifically to the birth of Jesus Christ. C." stands for "before Christ." In English, it is common for "A.
The idea would not spread to medieval Christian Europe, however, until the 11th to 13th centuries.
By the 15th century, all of Western Europe had adopted the B.
This goal had been decided upon by Constantine the Great at the Council of Nicea in 325 CE but had not yet been met.
Toward this end, Dionysius changed the system of dating years from the Roman system and the Alexandrian system to his own in which his present era dated from the birth of Jesus of Nazareth.
There is no biblical authority for BC/AD; it was created over 500 years after the events described in the Christian New Testament and was not accepted usage until after another 500 years had passed.
The use of BCE/CE certainly has become more common in recent years but it is not a new invention of the "politically correct" nor is it even all that new; the use of "common era" in place of A. first appears in German in the 17th century CE and in English in the 18th.
Prior years were numbered to count backward to indicate the number of years an event had occurred “before Christ” or “B.
After all, to Bede, zero didn’t exist.” However, zero exist; our modern conception of zero was first published in A.
The use of this designation in dating has nothing to do with "removing Christ from the calendar" and everything to do with accuracy when dealing with historical events.