Further questions on the same topic --
When was it decided that year 1 was year 1? At the time or several years later? What was used prior?
When/How did every civilization/society eventually agree on when year 1 started? This seems like it would be highly contested but obviously became globally accepted.
Hi there -- not to discourage further discussion, but the section of our FAQ on Calendars and timekeeping may be of interest to you.
Where in 10 BCE? There really wasn't a common calendar even within most empires.