Question

What happened in history to turn B.C. to A.D.

Answer 1

Hi There, The answer to your Question is

Step-by-step explanation:

This calendar era is based on the traditionally reckoned year of the conception or birth of Jesus, with AD counting years from the start of this epoch and BC denoting years before the start of the era. There is no year zero in this scheme, so the year AD 1 immediately follows the year 1 BC.

I hope it helped.

Answer 2

The Birth of Christ. For non-Christians they may say BCE and CE instead of BC and AD.