The Name of the Pope

It is common practice for popes of the Roman Catholic Church to take a new name—called their regnal name—upon elevation to the Throne of Peter. They will usually offer a reason for the new name. Cardinal Albino Luciani took the names of both his immediate predecessors and called himself Pope John Paul I. When he died after a very short (33 days) reign, Cardinal Karol Wojtyla chose to honor him by taking the name Pope John Paul II upon his accession.

Pope "Mercurius"

It hasn't always been thus, however. Whereas now almost all popes take the name of a saint, early popes used their own names—names that were not always common. So you had popes named Anacletus, Evaristus, Telesphorus, Hyginus, Soter, Eleuterus, Zephyrinus and others among the more common names like Felix and Boniface and John; and they only rarely needed numbers next to their names, because the likelihood of there being more than one pope named "Anterus" or "Eutychian" or "Miltiades" was slight.

The practice of taking a new name began not to honor a predecessor, however, but to avoid an embarrassment.

After the death of Pope Boniface II in October 532, there was a two-month vacancy in the position. Part of the reason for this was a (ahem) change in the process. You see, it had become common for some candidates to ensure their election through bribes and gifts. The Roman Senate forbade this practice just before the death of Boniface. Athalaric, the King of the Ostrogoths in Italy, upheld the Senate's decision, and added his own flourish: a disputed papal election that needed to come before his court would be fined 3000 solidi (a solidi was a gold coin of 4.5 grams) and the money given to the poor.

The cardinals fell into agreement on a distinguished priest of Rome, aged about 60. He was willing to take the job, but he had one concern. His Roman parents had given him a theophoric birth name—a name that honors a god in order to impart luck and protection to a child. His name was Mercurius. Father Mercurius did not think it was appropriate for a Christian pope to bear the name of a Roman god. He decided to take the name of a pope from a decade earlier who had had a good working relationship with Athalaric's grandfather.

And so Father Mercurius became Pope John II, the first pope known to have taken a new name upon election.