Pope Francis is appearing on the balcony over St. Peter's Square to wild cheers from the crowd below.
A list of popes from the 20th and 21st centuries:
Pope Francis — March 13, 2013-
Benedict XVI — April 19, 2005-Feb. 28, 2013.
John Paul II — Oct. 16, 1978-April 2, 2005.
John Paul I — Aug. 26-Sept. 28, 1978.
Paul VI — June 21, 1963-Aug. 6, 1978.
John XXIII — Oct. 28, 1958-June 3, 1963.
Pius XII — March 2, 1939-Oct. 9, 1958.
Pius XI — Feb. 6, 1922-Feb. 10, 1939.
Benedict XV — Sept. 3, 1914-Jan. 22, 1922.
Pius X — Aug. 4, 1903-Aug. 20, 1914.
Leo XIII — Feb. 20, 1878-July 20, 1903.
Argentine Cardinal Jorge Bergoglio is elected pope — and he is the first pontiff from the Americas.
He has chosen the name Pope Francis.
The conclave might have been quick - but not quick enough for some newspaper editors in Europe, who bemoaned the late hour as they tried to ready their next day's editions.
As the wait for the next pontiff to appear on the balcony dragged on, Archie Bland, deputy editor of The Independent in London, tweeted: "God clearly punishing newspapers with the timing here. Was the internet not enough?"
Peter Spiegel, Brussels bureau chief for the Financial Times, echoed Bland's sentiments. "Can someone please tell the new pope the (at)FT is about to miss it's 1st European deadline? (hash)HurryUp" he tweeted.
WHITE SMOKE OR NOT?
In St. Peter's Square, there was a fleeting moment of indecision when the first plumes of smoke appeared from the Vatican chimney.
Some cried out that it was black, signifying that no decision was made by the conclave. Then, seconds later under a steady rain, it became clear that white smoke was pouring out.
Wild cheering erupted in the square.
"Oh no, it's black!" said an Italian nun, Sister Eugenia. "It's white! It's white!'
Ben Canete, a 32-year-old Filipino, jumped up and down shouting: "Viva il Papa!"
"I can't explain how happy I am right now," he said.
'LONG LIVE THE POPE'
Throngs in St. Peter's Square are chanting "Long live the pope!," many of them with tears in their eyes.
There are least 50,000 people in the square. Crowds went wild as the Vatican and Italian military bands marched through and up the steps of the basilica, followed by Swiss Guards in silver helmets and full regalia.
They played the introduction to the Vatican and Italian anthems and the crowd joined in, waving flags from around the country.
CHOOSING A NAME
Every time a new pontiff is chosen in a conclave, a senior cardinal goes up to him and asks: "And by what name do want to be called?"
The question is popped immediately, while all electors are still locked in the Sistine chapel. So the winner had better have done his homework and already picked a name.
Shortly after, the senior cardinal reads out the pontifical name in Latin from the main balcony of St. Peter's Basilica as part of the "Habemus Papam" — "We have a pope" — formula that proclaims the election of a new pope.
The new pope can't move into the papal apartment just yet.
He will remain with the cardinals at the Vatican's Santa Marta hotel, an impersonal modern hotel on the edge of the Vatican gardens where they have been sequestered since the beginning of the conclave.
He will spend his first night as pontiff in a room that features a bed with a dark wood headboard and a carved image of Christ's face, as well as a sitting area and a study.
The new pope is expected to stay there for a few weeks until the papal apartment in the Apostolic Palace can be renovated. The apartment was sealed Feb. 28, just after Benedict resigned, and cannot be reopened until the new pope formally takes possession.
The pope's Twitter account, whose profile was changed to read "Sede Vacante" when Benedict stepped down, now has been switched back to "Pontifex."
No tweets yet.
The pope's new clothes were ready before he was.
The family-owned Gammarelli tailor shop, which has dressed popes for two centuries, had three sets of vestments — in small, medium and large — prepared for the naming of the new pontiff.
The papal outfits were on display in the window of the small wood-paneled store nestled in the shadow of the Pantheon, where the family moved in 1850 from the original founded just around the corner in 1798. They were delivered to the Vatican and left in a room next to the Sistine Chapel, ready for the new pope to change into his new clothes.
The pre-made looks haven't always fit. In 1958, the rotund John XXIII appeared on the balcony with safety pins holding together the back of his cassock.
It was a fairly quick decision.
In centuries past, conclaves dragged on for weeks and months, sometimes years. During a 13th-century conclave that stretched for weeks, a leading candidate died.
These days the discussions are much quicker. The pope was chosen in five rounds over two days.
The previous conclave that chose Benedict XVI went four rounds over two days before the Latin announcement rang out across St. Peter's Square from the basilica's balcony: "Habemus papam" — We have a pope!
The longest conclave of the last century went on for 14 rounds over five days, and yielded Pius XI — in 1922.
WHO VOTED FOR ME?
One thing is sure — the new pope will never truly know who voted for him.
Cardinals used to sign their names to ballots, but stopped doing so "due to an old history of intrigues and tensions, when people used to fear the most serious reprisals for their choices," says Michael Bruter, who teaches political science at the London School of Economics.
Even so, factions of cardinals will have made their views known during informal talks between votes.
Romain Lachat, a political scientist at Pompeu Fabra University in Barcelona, says the formation of coalitions — where voting cardinals slowly rally around a man who may only be their second or third choice — is inevitable.
There is no formal process of elimination and cardinals can even vote for themselves — which may explain why conclaves often need more than one round of balloting to produce a pope.
THE BIG SMOKE
The ballots are tied together with needle and thread and are then placed in an iron stove. If the smoke coming out of the chimney is white — not black — it means there's a pope.
The signal hasn't always been so clear. In 1958, damp straw didn't catch fire, and the smoke was white instead of black. After John Paul's death in 2005, the Vatican used special chemicals in an effort to make the color clear — with only limited success.
If in doubt, the bells of St. Peter's Basilica also ring when a new pope has been chosen.
Throngs of the faithful are in St. Peter's Square, ready to cheer the new pope when he steps out onto the balcony of St. Peter's Basilica. The vast square in Rome is a sea of umbrellas, flags and chanting crowds.
The Vatican's security force, known as the gendarmerie, is in charge of those inside the square, while Italian police handle crowd control just outside the Vatican's boundaries. Security officers from both forces include plainclothes agents dressed up as tourists, watching for any unusual movement.
A tented field hospital went up near the Vatican before the conclave began.
There have been a few "trial runs" of crowd control. Pope Benedict XVI's public audience drew so many people — some 150,000 — that there wasn't enough space for all in the cobblestone square.
The 266th pope has been chosen.
Whoever he may be, he now changes into his papal white cassock, and one-by-one the cardinals approach him to swear their obedience.
He will stop and pray in the Pauline Chapel for a few minutes before emerging on the loggia of the balcony overlooking St. Peter's Square.
Preceding him to the balcony is French Cardinal Jean-Louis Tauran, the protodeacon, who announces "Habemus Papam!" Latin for "We have a pope" and then introduces him to the world in Latin.
He then emerges and delivers his first public words as the leader of the world's 1.2 billion Catholics.
White smoke is pouring out from the Sistine Chapel chimney in St. Peter's Square, signaling that a new pope will appear on the balcony of St. Peter's Basilica within the hour.