• In the wake of the pope’s death, the College of Cardinals will soon have to dive headfirst into the notoriously secretive task of selecting the next head of the Catholic Church
• If traced back to its Latin roots, the term “conclave” translates roughly to “under lock and key,” according to Kathleen Sprows Cummings, a nationally recognized Pope Francis expert tells PEOPLE
• “There’s very, very distinct rules,” she says: Here’s how it works

As the world’s Catholics mourn Pope Francis in the wake of his death on Monday, April 21, the College of Cardinals has to dive headfirst into the notoriously secretive task of selecting the next head of the Catholic Church. 

This meeting is called a conclave, a seldom-used term by nature — the assembly only occurs when a pope dies — that recently saw a surge of use thanks to the 2024 Best Picture nominee of the same name.

Now, cardinals will soon be flocking to Rome for the real-life thing, and an expert is here to pull back the curtain a bit on the private process, which ends with smoke billowing from the Sistine Chapel — and, of course, a new pope-elect.

If traced back to its Latin roots, the term “conclave” translates roughly to “under lock and key,” according to Kathleen Sprows Cummings, a nationally recognized Pope Francis expert and professor of American Studies and History at the University of Notre Dame.

“So, the proceedings of the conclave are secret,” Cummings tells PEOPLE — though “invariably things leak out,” she adds, citing the meeting that led to Francis’ papacy over a decade ago.

A group of cardinals gathered in Rome. Stefano Spaziani/Europa Press via Getty 

The deliberations — which, at least in theory, are completely private — typically begin around 15 to 20 days after the death of a sitting pope and after the College of Cardinals has convened in Rome, per Cummings.

The gathering does not end until the next pontiff is selected.

Notably, the exclusive process is preceded by “these things called general congregations,” in which all of the cardinals — not just those eligible to vote — gather to “speak about what the church needs in the new Pope,” Cummings says.

A group of cardinals gathered in the Vatican in 2022. Corbis/Corbis via Getty 

Following those “general congregations,” the voting cardinals (of which there are currently 135) will then “enter a conclave in the Sistine Chapel,” Cummings continues, “and they will be sequestered there until they have a pope.”

Before voting can begin, the cardinals will pray for guidance.

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“There’ll be a Mass presided over by the dean of the College of Cardinals,” Cummings says. This title is currently held by a 91-year-old Italian cardinal, Giovanni Battista Re — who is actually unable to vote due to his age.

“Once you turn 80, you’re not eligible to vote for a pope,” Cummings adds.

The first ballot usually takes place that first night — and typically “many different” potential popes will get votes, she says.

White smoke billowing from the Sistine Chapel in 2013, marking Pope Francis’ selection as the next pope. Michael Kappeler/picture alliance via Getty

“There’s very, very distinct rules” for the voting and Cummings says the cardinals who can cast ballots “will continue to vote until they reach a two thirds majority.”

In 2013, Francis — who was not considered a front-runner — was elected on the fifth ballot, which was cast the day after the conclave began.

“After each vote,” Cummings explains, “smoke is sent up the chimney and it’s black. If it’s black, it means they have not elected a pope.”

White smoke, by contrast, signifies the end of the conclave, and “means that we have a new pope,” a signal which is followed by the official announcement, or “Habemus papam” — a Latin phrase that directly translates to, “We have a pope.”