Throughout history, the entry of a new Pope has been followed by a change of name by the new pontiff.
The custom of adopting a new name upon assuming the papacy dates back to the sixth century.
The first recorded case was that of Pope John II, whose birth name was Mercury, after the Roman god.
Considering it inappropriate to bear a pagan name as the leader of the Church, he chose to change it to John II, thus marking the beginning of this tradition.
