THE second longest-serving pope in history, John Paul II, who died in office in 2005 at the age of 84, has rather habituated us of late to the idea that popes are expected to carry on until they pop off. And it is true that while diocesan bishops must resign once they reach 75 and cardinals can no longer join a conclave past 80, no such rules apply to the Bishop of Rome and Supreme Pontiff of the Universal Church (to name just two of the pope’s titles).

But popes can, and do, resign. Not often, but they do. Back in 1045, the irredeemably outrageous Benedict IX - the only man to be pope more than once, and the only one ever to sell the papacy - stepped down, essentially for the cash. Accused by St Peter Damian of “feasting on immorality”, by Bishop Benno of Piacenza of committing “many vile adulteries and murders” and by Pope Victor III of being a pope “so vile, so foul, so execrable, that I shudder to think of it,” Benedict ostensibly resigned to get married - but not before he had sold the office to his godfather, who became Gregory VI (and had to resign himself the following year because, even by the standards of the 11th century, buying the papacy wasn’t really on).

More edifying is the case of Celestine V in 1294. A former Benedictine hermit, Celestine had never wanted to be pope. After a mere five months in office he issued a solemn decree declaring it permissible for a pope to resign and then promptly did so himself, citing “the desire for humility, for a purer life, for a stainless conscience, the deficiencies of his own physical strength, his ignorance, the perverseness of the people, his longing for the tranquility of his former life”.

His successor, Boniface VIII, however, refused to allow him to return to a life of solitary contemplation and instead had him locked up in the castle of Fumone, where he died in May 1296 (some suggest Boniface had him murdered).

The last pope to stand down was Gregory XII, who did so in 1415 to end the damaging Western schism, the split that divided the Catholic church for nearly 40 years and had, by the stage Gregory did the decent thing, reached the point where there were three different claimants to the papal throne: Roman Pope Gregory XII, Avignon Antipope Benedict XIII, and Pisan Antipope John XXIII.

Since then, a couple of popes - Pius VII and Pius XII - reportedly signed documents of resignation that were to take effect if they were ever kidnapped and imprisoned by (respectively) the French or the Nazis. So while Pope Benedict XVI’s announcement of resignation on Monday was a shock, it is not entirely unprecedented.

By arrangement with the Guardian