When I see a Julian date such as April 1, 5 B.C. what would that be in Gregorian format? I just do not understand how I am to relate a Julian date in history. If someone says something happened in April 1, 5 B.C. Julian date, how am I to relate to it in Gregorian terms? <br />If a historian says that Cyrus conquered Babylon in 540 B.C. I assume that is in Gregorian date format.