From Saint Peter in 32 C.E. to Benedict XVI in 2005, there have been 266 officially recognized popes in the Catholic church. Of these, only a handful were known to step down from the position; the last one to do so, before Benedict XVI, was nearly 600 years ago. The first pope to abdicate did so almost 1800 years ago.
The history of the popes was not always clearly chronicled, and some of what was recorded has not survived; thus, there is much we don't really know about many popes through the first few hundred years C.E. Some popes were charged by later historians with abdicating, though we have no evidence; others stepped down for reasons unknown.
Here is a chronological list of popes who resigned, and some who may or may not have given up their post.
Elected: July 21, 230
Resigned: September 28, 235
Died: c. 236
Pope Pontian, or Pontianus, was a victim of the persecutions of Emperor Maximinus Thrax. In 235 he was sent to the mines of Sardinia, where he was no doubt poorly treated. Separated from his flock, and realizing he was unlikely to survive the ordeal, Pontian turned over the responsibility of leading all Christians to St. Anterus on September 28, 235. This made him the first pope in history to abdicate. He died not long after; the exact date and manner of his death are unknown.
Elected: June 30, 296
Died: October, 304
In the first few years of the fourth century, a vicious persecution of Christians was begun by the emperor Diocletian. The pope at the time, Marcellinus, was believed by some to have renounced his Christianity, and even to have burned incense for Rome's pagan gods, in order to save his own skin. This charge was refuted by St. Augustine of Hippo, and no real evidence of the pope's apostasy has been found; so the abdication of Marcellinus remains unproven.
Elected: May 17, 352
Died: September 24, 366
By the mid-fourth century, Christianity had become the official religion of the empire. However, emperor Constantius II was an Arian Christian, and Arianism was considered heresy by the papacy. This put Pope Liberius in a difficult position. When the emperor interfered in Church matters and condemned Bishop Athanasius of Alexandria (a staunch opponent of Arianism), Liberius refused to sign the condemnation. For this Constantius exiled him to Beroea, in Greece, and an Arian cleric became Pope Felix II.
Some scholars believe that the installation of Felix was made possible only by the abdication of his predecessor; but Liberius was soon back in the picture, signing papers negating the Nicene Creed (which condemned Arianism) and submitting to the authority of the emperor before returning to the papal chair. Constantius insisted Felix continue, however, and so the two popes co-ruled the Church until the death of Felix in 365.
John XVIII (or XIX)
Elected: December, 1003
Died: June, 1009
In the ninth and tenth centuries, powerful Roman families became instrumental in getting many of the popes elected. One such family were the Crescentii, who engineered the election of several popes at the end of the 900s. In 1003, they maneuvered a man named Fasano onto the papal chair. He took the name John XVIII and reigned for 6 years.
John is something of a mystery. There is no record of his abdication, and many scholars believe he never stepped down; and yet it is recorded in one catalogue of popes that he died as a monk at the monastery of St. Paul, near Rome. If he did choose to give up the papal chair, when and why he did so remains unknown.
The numbering of popes named John is uncertain because of an antipope that took the name in the 10th century.
Forced on the cardinals as pope: October, 1032
Run out of Rome: 1044
Returned to Rome: April, 1045
Resigned: May, 1045
Returned to Rome again: 1046
Officially deposed: December, 1046
Installed himself as pope for a third time: November, 1047
Removed from Rome for good: July 17, 1048
Died: 1055 or 1066
Placed on the papal throne by his father, Count Alberic of Tusculum, Teofilatto Tusculani was 19 or 20 when he became Pope Benedict IX. Clearly not suited for a career in the clergy, Benedict enjoyed a life of licentiousness and debauchery for more than a decade. At last the disgusted Roman citizens revolted, and Benedict had to run for his life. While he was gone, the Romans elected Pope Sylvester III; but Benedict's brothers drove him out a few short months later, and Benedict returned to take up the office again. However, now Benedict grew tired of being a pope; he decided to step down, possibly so that he might marry. In May of 1045, Benedict resigned in favor of his godfather, Giovanni Graziano, who paid him a hefty sum.
You read that right: Benedict sold the papacy.
And yet, this would not be the last of Benedict, the Despicable Pope.
Elected: May, 1045
Resigned: December 20, 1046
Died: 1047 or 1048
Giovanni Graziano may have paid for the papacy, but most scholars agree he had a sincere desire to rid Rome of the abominable Benedict. With his godson out of the way, Graziano was recognized as Pope Gregory VI. For about a year Gregory tried to clean up after his predecessor. Then, deciding he'd made a mistake (and possibly unable to win the heart of his beloved), Benedict returned to Rome -- and so did Sylvester III.
The resulting chaos was too much for several high-ranking members of the clergy and citizens of Rome. They begged King Henry III of Germany to step in. Henry agreed with alacrity and traveled to Italy, where he presided at a council in Sutri. The council deemed Sylvester a false claimant and imprisoned him, then officially deposed Benedict in absentia. And, though Gregory's motives had been pure, he was persuaded that his payment to Benedict could only be viewed as simony, and he agreed to resign for the sake of the papacy's reputation. The council then chose another pope, Clement II.
Gregory accompanied Henry (who'd been crowned Emperor by Clement) back to Germany, where he died several months later. But Benedict did not go away so easily. After Clement's death in October, 1047, Benedict return to Rome and installed himself as pope one more time. For eight months he remained on the papal throne, until Henry drove him out and replaced him with Damasus II. After this, Benedict's fate is uncertain; he may have lived another decade or so, and it is possible he entered the monastery of Grottaferrata. No, seriously.
Elected: July 5, 1294
Resigned: December 13, 1294
Died: May 19, 1296
In the late 13th century, the papacy was plagued by corruption and financial problems; and two years after the death of Nicholas IV, a new pope still hadn't been nominated. Finally, in July of 1294, a pious hermit by the name of Pietro da Morrone was elected in the hopes that he could lead the papacy back to the right path. Pietro, who was close to 80 years old and longed only for solitude, was not happy to be chosen; he only agreed to occupy the papal chair because it had been vacant for so long. Taking the name Celestine V, the devout monk attempted to institute reforms.
But though Celestine is almost universally considered a saintly man, he was no administrator. After struggling with the problems of papal government for several months, he at last decided it would be best if a man more suited to the task took over. He consulted with the cardinals and resigned on December 13, to be succeeded by Boniface VIII.
Ironically, Celestine's wise decision did him no good. Because some did not think his abdication was lawful, he was prevented from returning to his monastery, and he died sequestered in Fumone Castle in November of 1296.
Elected: November 30, 1406
Resigned: July 4, 1415
Died: Oct. 18, 1417
At the end of the 14th century, one of the strangest events ever to involve the Catholic Church took place. In the process of bringing about an end to the Avignon Papacy, a faction of cardinals refused to accept the new pope in Rome and elected a pope of their own, who set up back in Avignon. The situation of two popes and two papal administrations, known as the Western Schism, would last for decades.
Although all concerned wanted to see an end to the schism, neither faction was willing to allow their pope to resign and let the other take over. Finally, when Innocent VII died in Rome, and while Benedict XIII continued as pope in Avignon, a new Roman pope was elected with the understanding that he would do everything in his power to end the break. His name was Angelo Correr, and he took the name Gregory XII.
But although the negotiations that proceeded between Gregory and Benedict looked hopeful at first, the situation rapidly degenerated into one of mutual distrust, and nothing happened -- for more than two years. Filled with concern over the lingering break, cardinals from both Avignon and Rome were moved to do something. In July, 1409, they met at a council in Pisa to negotiate an end to the schism. Their solution was to depose both Gregory and Benedict and to elect a new pope: Alexander V.
However, neither Gregory nor Benedict would acquiesce to this plan. Now there were three popes.
Alexander, who was about 70 years old at the time of his election, lasted only 10 months before passing away under mysterious circumstances. He was succeeded by Baldassare Cossa, a cardinal who had been a leading figure at the council at Pisa and who took the name John XXIII. For four more years, the three popes remained deadlocked.
At last, under pressure from the Holy Roman Emperor, John convoked the Council of Constance, which opened on November 5, 1414. After months of discussion and some very complicated voting procedures, the council deposed John, condemned Benedict, and accepted Gregory's resignation. With all three popes out of office, the way was clear for the cardinals to elect one pope, and one pope only: Martin V.
Elected: April 19, 2005
Set to resign: February 28, 2013
Unlike the drama and the stress of the medieval popes, Benedict XVI is resigning for a very straightforward reason: his health is frail. In the past, a pope would hang onto his position until he drew his last breath; and this wasn't always a good thing. Benedict's decision seems rational, even wise. And though it struck many observers, Catholic and non-Catholic alike, as a surprise, most people see the logic and support Benedict's decision. Who knows? Perhaps, unlike most of his medieval predecessors, Benedict will survive more than a year or two after giving up the papal chair.