Two hundred sixty-six popes have led the Roman Catholic Church since Jesus of Nazareth founded it around A.D. 33. 

But how did they get the job? And what did it lead them to do?

Many of the answers are surprising.

Below is a list of firsts and lasts when it comes to choosing a new pope. 

Many of the facts below come from historian Frederic Baumgartner’s 2003 book Behind Locked Doors: A History of the Papal Elections, published by Palgrave Macmillan. 

First Pope to Take a Different Name 

When Mercurius was elected bishop of Rome in 532, he faced an immediate problem. While there has been a third-century Christian martyr with the same name, most people associated it with Roman mythology. 

So he decided to take a new name, becoming Pope John II.

“His name was Mercurius, and he became John to avoid polluting the papacy with the name of a pagan god …” Baumgartner wrote in Behind Locked Doors.

Mercurius/John II thus became the first pope to pick a new name upon being elected bishop of Rome. (St. Peter, the first pope, also took on a new name (in Matthew 16:17-18), but Jesus picked it for him.)

The idea of taking a new name didn’t take root right away, however, and most of John II’s successors during the next 464 years kept their own name after becoming pope. 

Bruno of Carinthia (in what is now Austria) took the name Gregory V upon being elected pope in 996, starting the nearly unbroken tradition of a pope taking a new name upon election. Almost all popes during the last 1,029 years have followed suit. 

Last Pope to Keep His Own Name 

Pope Marcellus II — born Marcello Cervini degli Spannocchi (1501-1555) — kept his given name as his regnal name upon being elected pope in 1555. He’s the last one to date. His reign lasted only 22 days. 

Marcellus II and his 16th-century predecessor Adrian VI (reigned 1522-1523) are the only popes since 996 to keep their given names as pope — if you don’t count the fictional Ukrainian cardinal elected as Pope Kirill in Morris West’s 1963 bestselling novel The Shoes of the Fisherman. 

All 44 actual popes since Pope Marcellus II have taken a regnal name that differs from their given name. 

First Pope From a Religious Order 

In 590, Pope Gregory I — also known as St. Gregory the Great — became the first monk elected pope.

Since then, Benedictines, Augustinians, Franciscans, Dominicans, Cistercians and one each from the Norbertines, Theatines and Jesuits (Pope Francis, 2013) have become pope. The vast majority, however, have served in a diocese as a priest and bishop before becoming pope.

Last Franciscan to Become Pope

Pope Clement XIV (reigned 1769-1774), a Conventual Franciscan, was the last spiritual son of St. Francis of Assisi to become pope. He is remembered, among other things, for suppressing the Jesuits in 1773.

Only two other Franciscans — Nicholas IV (reigned 1288-1292), from the Order of Friars Minor; and Sixtus IV (reigned 1471-1484), a Conventual Franciscan — have been elected pope.

In the May 2025 conclave, eight Franciscans are cardinal-electors, including Cardinal Pierbattista Pizzaballa, the Latin patriarch of Jerusalem, who is thought to be a serious candidate for pope. Cardinal Seán O’Malley, a Capuchin Franciscan and the archbishop emeritus of Boston, also makes some lists, although at age 80 he is too old to participate in the conclave.

First Time Cardinals Became the Only Official Electors of a Pope 

Cardinals appointed by a previous pope became the only electors of a pope in 1059 — 966 years ago.

Last Non-Cardinal to Become Pope

Archbishop Bartolomeo Prignano wasn’t a cardinal when a papal conclave in 1378 elected him pope, 647 years ago. He took the name Urban VII.

In 1513, Cardinal Giovanni di Lorenzo de’ Medici became the last non-priest to be elected pope. At the time, it was not uncommon for a layman to be a cardinal. Pope Leo X, as he called himself, was ordained a priest and then ordained a bishop.

Nowadays, in theory, any baptized Catholic male can be elected pope, but canon law (332) provides that if the man elected is not already a bishop “he is to be ordained a bishop immediately.”

All 49 popes elected since Leo X have been both a cardinal and a bishop at the time of their election.

In the May 2025 papal conclave, only one of the cardinal-electors, Cardinal Timothy Radcliffe, 79, a Dominican priest and theologian from England, is not a bishop. 

First Time a Pope Was Crowned 

Pope Nicholas I — known as Nicholas the Great to his friends — was crowned after being elected pope in 858. He’s believed to be the first pope to wear a crown.

The crown reflected the temporal authority of popes, who ruled a sizeable portion of central Italy (known as the Papal States) much of the time between 756 and 1870.

In 1059, Pope Nicholas II was the first pope crowned in a ceremony that incorporated elements of the coronation of a Byzantine emperor, according to Baumgartner’s book.

Last Time a Pope Was Crowned

Pope Paul VI was the last pope to be crowned, in 1963. But Paul VI sold his coronation triple tiara for charity — and it ended up in the Basilica of the National Shrine of the Immaculate Conception in Washington, D.C., where it is on display.

In August 1978, John Paul I rejected a coronation after being elected pope, opting for a simpler inauguration instead. His three successors to date all followed suit.

First Time a Man Elected Pope Said ‘No’ 

A candidate named Adrian is the first candidate known to have refused the papacy, in 855, according to Baumgartner’s Behind Locked Doors. Pope Benedict III was elected after Adrian’s refusal. 

Last Time a Man Elected Pope Said ‘No’

In 1187, Cardinal Theobald of Ostia was reportedly elected pope but refused it, leading to the eventual election of Pope Clement III.

Since then, on occasion, certain plausible candidates have taken themselves out of consideration before securing the necessary two-thirds majority, although because of official secrecy rules such instances in modern times are hard to verify.

These days, a candidate doesn’t become pope until the cardinal-electors elect him and he says “Accepto” — Latin for “I accept.” If he says “No,” the conclave continues. 

First Time a Pope Was Elected by a ‘Conclave’ 

The papal election of 1241 was the first time cardinal-electors were locked in a room to elect a new pope — thus the first conclave, which comes from the Latin cum and clave, meaning “with a key.”

This method — which at times included increasing severities such as limiting food and beverages and even, at one point in 1270, removing the roof — was used because cardinals during the Middle Ages sometimes took too long to decide, in the opinion of public officials and the people.

Last Time a Conclave Took Years to Elect a Pope 

Divisions among cardinals led the conclave of 1314-1316 to last about two years two months, before electing Pope John XXII.

The longest conclave ever lasted two years nine months — from 1268 to 1271. It produced Pope Gregory X.

The last time a conclave lasted more than five days was 1830-1831, when the cardinals elected Pope Gregory XVI after 50 days.

First Time a Pope Took a Double Name

In August 1978, when Cardinal Albino Luciani, the patriarch of Venice, was elected pope, he took a double name — John Paul — to honor his two most recent predecessors.

It was the first time a pope took more than one name as his regnal name.

He also broke with tradition by calling himself John Paul I (“John Paul the First”), using a regnal number even though he was the first to use that name, which is something popes and kings usually don’t do.

He died after just 33 days. That’s the 11th-shortest reign of a pope.

The shortest reign is that of Pope Urban VII in 1590 — just 13 days.

Last Time a Pope Took a Double Name

The papal conclave of October 1978 shocked observers by electing the first pope from Poland: Cardinal Karol Wojtyla, archbishop of Krakow.

He reportedly would like to have taken for his regnal name Stanislaus, after the 11th-century Polish bishop and martyr who also led the then-Diocese of Krakow.

Instead, he picked John Paul II, to honor his immediate predecessor as well as Pope John XXIII and Pope Paul VI, who, respectively, started and ended the Second Vatican Council (1962-1965).

He’s not the only pope who reportedly preferred a different name from the one he ended up with.

In 1464, when Cardinal Pietro Barbo was elected pope, he announced that he wanted to call himself Formosus II. But the cardinal-electors objected on the grounds “that the word means handsome in Latin,” Baumgartner wrote in Behind Locked Doors, “and Barbo was known for his vanity about his appearance.”

He became Paul II instead. 

First Time Smoke Meant Something

In 1823, smoke from a chimney during a papal conclave signaled to the crowd in Rome that no pope had been elected — apparently for the first time.

“It is difficult to prove a negative,” noted Baumgartner in Behind Locked Doors, but he said that no source he found about papal elections before 1823 (when Pope Leo XII was elected) mentions smoke. 

No significance would be attached to the color of the smoke until 91 years later, in 1914. 

That year, white smoke signaled the election of a new pope (Benedict XV) for the first time, according to Baumgartner’s book, which devotes an appendix to the subject of smoke.

“Perhaps the principal reason for this development was Pius X’s mandate that all papers relating to the election be burned, not just the ballots themselves, thus producing a great deal more white smoke for the final ballot and making it truly visible,” Baumgartner wrote.

The smoke signals have proved frustrating at times, with smoke appearing white before turning black in the 1939 and 1958 conclaves. In the 1963 conclave, Vatican officials started adding chemicals to try to ensure that the smoke from the final ballot appears white when it comes out of the chimney of the Sistine Chapel — with mixed reviews. 

Last Time a Secular Ruler Vetoed a Candidate for Pope

The secrecy that engulfs papal elections nowadays stems from attempts by outsiders to influence the cardinal-electors — something that happened routinely during the Middle Ages.

And not that long ago, too.

In 1903, the cardinals in the papal conclave were reportedly on the verge of electing Cardinal Mariano Rampolla of Sicily as pope when the emperor of Austria, Francis Joseph I, vetoed the selection through a Polish cardinal — a right that Catholic heads of state in Europe had claimed at least since the 16th century, according to the Catholic Encyclopedia of 1908. Cardinal Giuseppe Sarto was elected instead of Cardinal Rampolla and took the name Pius X. 

The following year, Pius X issued two apostolic constitutions (Commissum Nobis and Vacante Sede Apostolica) denying a veto to anybody outside of a papal conclave and threatening excommunication of any cardinal who tried to deliver such a veto.