How many years ago was the Common Era?

A:The Common Era, or Christian Era, begins with the life of Jesus. The Roman abbot Dionysus Exiguus, who devised the new Christian calendar in 533, knew that he could not say when Jesus was born but he believed he knew when King Herod had died. So he devised a new calendar system, starting the Common Era (CE) with the death of Herod. His misunderstanding of the reign of Caesar Augustus meant that he began his calendar just four years to late, as King Herod really died in April 4 BCE.