Who will be the next pope? Here's how the conclave works

A giant monitor in St. Peter's Square at the Vatican, Tuesday, March 12, 2013 shows the heavy wooden door to the Sistine Chapel being closed and locked, signaling the start of the conclave to elect a new pope to succeed Benedict XVI following his stunning resignation. (AP Photo/Gregorio Borgia, File)

The white smoke is famous. When it streams out of a chimney at the Sistine Chapel, it signals that a new pope has been chosen and sets off celebrations among some 1.4 billion Catholics around the world.

Behind the scenes, a mysterious and intensely dramatic process culminates in that smoke — literally. It’s created by burning the ballots cardinals just used. White smoke signals that the Roman Catholic Church has a new leader; black smoke means the cardinals will need to vote again.

With the death of Pope Francis, the elaborate mechanism will now begin to decide who sits in power at the Vatican, the seat of the last absolute monarchy in Europe. It centers around the conclave, a gathering whose name stems from the Latin for “with key.”

“That actually comes from the 13th century,” Bry Jensen, host of the long-running Pontifacts podcast, tells NPR. She says cardinals couldn’t agree on a new pope in 1268 and the Church went nearly three years without a pontiff, despite growing frustration outside the cardinals’ ranks.

“They locked the cardinals up behind closed doors, and then they put them on water and bread so that they would focus on the essentials,” says Kurt Martens, ordinary professor of Canon law at the School of Canon Law at the Catholic University of America.