An audience with the pope is a day to remember.

But only on Capitol Hill would the day after the pope visited become even more memorable.

The late Pope Francis came to Washington, D.C., to speak to a Joint Meeting of Congress on Sept. 24, 2015. He wasn’t the first pontiff to descend on Capitol Hill. But the pope is a head of state, ruling the Vatican City and the Holy See. As such, Francis became the first pope to speak to a Joint Meeting of Congress in the House chamber.

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Pope Francis leads his traditional Wednesday General Audience at St. Peter’s Square in Vatican City on March 8, 2023.  (Stefano Costantino/SOPA Images/LightRocket via Getty Images)

Lawmakers showered the Holy Father with applause and two standing ovations during his address. Two Catholics were perched behind Pope Francis on the dais: then Vice President Joe Biden and former House Speaker John Boehner, R-Ohio. As vice president, Biden served as President of the Senate. As speaker, Boehner was the Constitutional officer for the legislative branch.

Boehner blotted his eyes with a handkerchief several times during the 3,400-word speech.

Pope Francis implored lawmakers to treat each other — and their constituents — with dignity.

«We need to avoid a common temptation nowadays. To discard whatever proves troublesome. Let us remember the Golden Rule: ‘Do unto others as you would have them do unto you,’» he said.

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President Joe Biden, left, exchanges gifts with Pope Francis as they meet at the Vatican on Oct. 29, 2021. (Vatican Media via AP)

One thing I remember about the Pope’s visit was the choreography. Congressional workers affixed small, green strips of tape to the Capitol’s marble floors. Names were emblazoned on the tape in black Magic Marker at different points around the complex. «McCarthy» or «Pelosi» or «McConnell.» All part of the political — and papal — stagecraft.

The tape dictated where key political leaders would stand as they escorted Pope Francis into the House chamber or in front of the statue of Junipero Serra in Statuary Hall.

A duct-taped «X» marked the floor in front of Serra. The pope canonized Serra the day before he visited the Capitol at the Basilica of the National Shrine of the Immaculate Conception in Washington. Serra became the first American to become a saint on U.S. soil. Pope Francis blessed the statue of Serra. The statue depicts the saint hoisting a cross in his right hand, looking skyward toward the heavens.

Someone taped a green arrow over the black and white tiles of Statuary Hall, pointing toward the Speaker’s Office.

That signaled the pope’s next stop on Capitol Hill.

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Pope Francis addresses the joint session of Congress in Washington, D.C., on Sept. 24, 2015. (Vincenzo Pinto/AFP via Getty Images)

Pope Francis and the entourage then walked toward Boehner’s office and onto the Speaker’s Balcony overlooking the West Front of the Capitol and down the National Mall toward the Washington Monument.

A throng assembled on the Capitol grounds.

«Buenos dias,» said the Pope, greeting the crowd like he would from the «Pope’s Window» at the Apostolic Palace at the Vatican on a Sunday. «I am grateful for your presence.»

He then blessed the pilgrims on the ground below.

«Papa! Papa!» the crowd chanted.

When the pope first arrived at the Capitol, he met with Boehner in the Speaker’s ceremonial office just off the House floor.

Boehner paced nervously awaiting Pope Francis on the 19th century Minton Tiles, which adorn the office.

«He’s on Boehner time,» said the former speaker. «Which is on time.»

Boehner wore his signature Kelly green tie for the occasion — a vintage piece of Boehner apparel, which dates back to when he served in the Ohio state legislature and first ran for Congress in 1990. When Pope Francis arrived, he told the former speaker the tie bore a «color of hope.»

A few days later, Boehner choked up as he relayed a story about what Pope Francis said to him when they were about to exit the Capitol.

«We found ourselves alone,» said Boehner of himself and Francis.

Pope Francis ponders during the inauguration of a UNESCO chair at the Pontifical Lateran University in Rome on Oct. 7, 2021. (Filippo Monteforte/AFP via Getty Images)

The pope grabbed the speaker’s arm.

«The pope puts his arm around me and kind of pulled me to him and said, ‘Please pray for me,’» said Boehner. «Wow. Who am I to pray for the pope?’ But I did.»

Boehner left the Capitol that night. But his encounter with the Holy Father seemingly transformed the speaker — and altered the trajectory of the House for years to come.

The speaker decided to resign the next morning.

«He had been trying to get out of here for years,» said one source close to the speaker at the time.

Boehner’s plans to depart were thwarted when the heir apparent, former House Majority Leader Eric Cantor, R-Va., stunningly lost his primary in the spring of 2014.

So Boehner soldiered on.

By late July 2015, former Trump White House chief of staff and former Rep. Mark Meadows, R-N.C., prepped a «motion to vacate the chair.» Those who follow Capitol Hill know all about such a motion now. But it was novel a decade ago. Such a motion would require the House to take a vote of confidence in the speaker in the middle of the Congress. Lawmakers had never used the tactic before. It was hardly discussed.

Pope Francis meets President Donald Trump in the Private Library of the Apostolic Palace in Vatican City on May 24, 2017. (Vatican/Pool/Galazka/Archivio Grzegorz Galazka/Mondadori via Getty Images)

Meadows released his resolution just before the August recess — but never triggered it.

That gave Boehner and the House a month to stew over whether Meadows might try to oust the speaker when lawmakers returned in September.

On the night after the pope’s visit, Boehner called his chief of staff, Mike Sommers, to tell him he planned to step aside. Boehner also told his wife, Debbie, of his plans.

«This morning I woke up, said my prayers, as I always do, and thought, ‘This is the day I am going to do this,’» said Boehner.

Boehner then astonished a meeting of the House Republican Conference that he intended to resign.

The move sent a shock wave through Washington.

«My first job as speaker is to protect the institution,» Boehner said. «It had become clear to me that this prolonged leadership turmoil would do irreparable harm to the institution.»

The Boehner departure — the day after his encounter with Pope Francis — set into motion what some might regard as the very «prolonged leadership turmoil» that the former speaker hoped to avoid.

It was believed that former House Speaker Kevin McCarthy, R-Calif. — then the House Majority Leader — would ascend to the job. But as startling as Boehner’s departure was, McCarthy supplanted that. Moments before House Republicans were set to tap McCarthy as the next speaker, McCarthy withdrew from the contest. He lacked the votes.

Rep. Kevin McCarthy, R-Calif., looks on at the U.S. Capitol in Washington, D.C., on Oct. 3, 2023. (Nathan Howard/Bloomberg via Getty Images)

McCarthy’s decision roiled Capitol Hill for weeks. Former House Speaker Paul Ryan, R-Wis., eventually took the job. But Ryan was reluctant. He even put out a statement that he didn’t want it.

Others jumped in: Rep. Daniel Webster, R-Fla., along with former Reps. Jason Chaffetz, R-Utah, and Bill Flores, R-Texas.

But Ryan finally came around. Fox was told at the time that if Ryan hadn’t come around, «there would be blood on the floor» of the House as Republicans waged an internecine donnybrook.

Ryan remained as House speaker until he retired in early 2019. Democrats won the House in the 2018 midterms. Former House Speaker Nancy Pelosi, D-Calif., returned to the speakership she held eight years before.

But Democrats lost the House in the 2022 midterms. And even though McCarthy touted a 40-plus-seat rout for the GOP, Republicans controlled the House by a thread.

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House Speaker Mike Johnson, R-La., left, and former House Speaker Kevin McCarthy, R-Calif. (Getty Images)

Thus, it set into motion a five-day battle in early 2023 as McCarthy struggled for 15 rounds before winning the speakership. It was the longest speaker’s race since the mid-19th century.

But McCarthy was gone by early November.

Remember that «motion to vacate the chair» mentioned earlier?

Meadows never activated his motion in 2015. But former Rep. Matt Gaetz, R-Fla., did in 2023.

McCarthy was done. And the House spent three weeks trying to elect a new speaker.

First they tried House Majority Leader Steve Scalise, R-La. Then House Judiciary Committee Chairman Jim Jordan, R-Ohio. Then House Majority Whip Tom Emmer, R-Minn.

None prevailed.

Finally, a backbencher emerged from the fray: House Speaker Mike Johnson, R-La.

Rep. Mike Johnson, a Republican from Louisiana, holds the gavel after being re-elected House speaker during the first session of the 119th Congress in the House Chamber of the Capitol in Washington, D.C., on Jan. 3. (Kent Nishimura/Bloomberg via Getty Images)

The House of Representatives has never quite been the same since Boehner made his surprise announcement after his encounter with Pope Francis. The speakership seems to teeter on an edge these days — at least when Republicans run the chamber. Johnson periodically endures threats to «vacate the chair.» Rep. Marjorie Taylor Greene, R-Ga., tried to bounce him just last year.

During the speaker succession fight of 2015 and the three-week speaker debacle of 2023, friends asked if «white smoke» would emanate from the Capitol Dome. They facetiously suggested that it would signal the election of a new House speaker.

The College of Cardinals will begin a conclave in Rome in a few days to select a successor to Pope Francis. It’s a political process. Not unlike what happens in Congress when there’s a vacancy in the speakership. We’ll know there’s a new pope when white smoke wafts out of a duct atop the Sistine Chapel.

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Cardinals of the Catholic Church attended the election conclave in the Sistine Chapel at the Vatican in Vatican City on April 18, 2005. (Arturo Mari, Vatican Pool)

It was an important day when Pope Francis spoke to a Joint Meeting of Congress in 2015. But in sheer Congressional terms, the day afterward was seismic for the nature of the institution. Boehner’s abrupt resignation ushered in an unsettled era about who presides over the House. The visit by Pope Francis and Boehner’s departure forever melded the two together in the annals of Capitol Hill.

And as a result, whenever there’s a House speaker interregnum in the future, political observers will always look for political «white smoke» to find out if lawmakers have settled on a new leader.