Rome CNN  — 

Pope Francis paid tribute to his predecessor former Pope Benedict XVI Thursday, in a funeral attended by tens of thousands of mourners at St. Peter’s Square.

The event marked the first occasion in modern times that a pontiff had presided over the funeral of his predecessor – and the first ever of one who resigned. Benedict, the first pontiff in almost 600 years to resign his position, rather than hold office for life, died aged 95 on December 31 at a monastery in Vatican City.

It was an occasion characterized by simplicity, as per the wish of the former pope. “It’s difficult to have a simple service in St. Peter’s Square, but I think it was,” Father James Martin, a Jesuit priest, writer and editor, told CNN’s Max Foster and Bianca Nobilo on CNN Newsroom.

“You have to have some pomp and ceremony for a former pope, but I think within the guidelines of what Pope Emeritus Benedict wanted, it succeeded very well.”

About 50,000 people attended the funeral in St. Peter’s Square according to Vatican spokesperson Matteo Bruni, with many members of the crowd calling for the late pope to be consecrated a saint.

The attendance compared with an estimated 1.1 million people for the funeral of Benedict’s predecessor, Pope John Paul II. There were 500,000 people in St. Peter’s Square and the surrounding area in 2005, and another 600,000 who watched on video screens in other parts of Rome.

John Paul II’s funeral was the largest gathering of heads of state ever outside the United Nations. Delegations included nine monarchs along with 70 presidents and prime ministers.

Over the six days between John Paul II’s death and his funeral, an estimated 3 million people came to pay their final respects. Each hour, 21,000 people passed through St. Peter’s Basilica. The average wait to see the pope was 13 hours, and at its maximum the line was 3 miles long.

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Mourners at the Vatican pay their respects to former Pope Benedict XVI as he lies in state inside St. Peter's Basilica on Tuesday, January 3.
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Pallbearers stand next to the coffin of former Pope Benedict as Pope Francis presides over the ceremonies, in St. Peter's Square at the Vatican, on January 5.
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Cardinal Giovanni Battista Re blesses the coffin of former Pope Benedict in The Holy Grotto of the Vatican.
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The coffin of former Pope Benedict is sealed with welding torches in The Holy Grotto of the Vatican.
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A view of St. Peter's Square with St. Peter's Basilica during the public funeral mass for Pope Emeritus Benedict XVI.
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Cardinal Giovanni Battista Re leads the funeral mass for former Pope Benedict, alongside Pope Francis, in St. Peter's Square at the Vatican.
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Priests prepare for the holy communion during the funeral mass.
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Tens of thousands of mourners attended the funeral mass.
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A mourner prays during the funeral service at the Vatican.
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Cardinals attend the funeral.
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Mourners attend the public funeral mass for Pope Emeritus Benedict XVI in St. Peter's Square, preceded by a member of the Pontifical Swiss Guard.
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Pope Francis sits behind the coffin of the late Pope Emeritus Benedict XVI during the public funeral mass in St. Peter's Square.
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Pope Francis attends the funeral mass of Pope Emeritus Benedict XVI.
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Pope Francis attends the funeral of former Pope Benedict in St. Peter's Square.
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Cardinal Giovanni Battista Re blesses the coffin of Pope Emeritus Benedict XVI during his funeral mass at St. Peter's Square in the Vatican.
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Belgium's Queen Mathilde and King Philippe, Italy's Prime Minister Giorgia Meloni, Italy's President Sergio Mattarella, German President Frank-Walter Steinmeier and his wife Elke Budenbender were among those attending the funeral of former Pope Benedict in St. Peter's Square at the Vatican.
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Pope Francis stands by the coffin of Pope Emeritus Benedict XVI during his funeral mass at St. Peter's Square in the Vatican.
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Pope Francis arrives during the funeral mass of Pope Emeritus Benedict XVI at St. Peter's Square in the Vatican.
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German Archbishop Georg Gaenswein kisses the coffin of Pope Emeritus Benedict XVI at the start of his funeral mass at St. Peter's Square in the Vatican.
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German Archbishop Georg Gänswein (R) stands by the coffin of the late Pope Emeritus Benedict XVI at the start of his funeral mass at St. Peter's Square.
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The coffin of former Pope Benedict is carried during his funeral, in St. Peter's Square at the Vatican.
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Georg Gänswein, archbishop of the Curia and longtime private secretary to the late Pope Emeritus Benedict XVI, attends the public funeral mass for Pope Emeritus Benedict XVI in St. Peter's Square.
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Italian President Sergio Mattarella arrives during the funeral mass of Pope Emeritus Benedict XVI at St. Peter's Square.
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The coffin of Pope Emeritus Benedict XVI is seen at the start of his funeral mass at St. Peter's Square in the Vatican, on January 5, 2023.
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Pallbearers carry the coffin of Pope Emeritus Benedict XVI at the start of his funeral mass at St. Peter's Square in the Vatican, on January 5.
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Members of the church wait for the funeral mass for late Pope Emeritus Benedict XVI to begin in St. Peter's Square at the Vatican, on January 5.
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Nuns read L'Osservatore Romano at St. Peter's Square on the day of the funeral of former Pope Benedict at the Vatican.
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Mourners watch over the body of Pope Emeritus Benedict XVI as he lies in state inside St. Peter's Basilica on Wednesday, January 4.
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Priests process through St. Peter's Basilica as Benedict lies in state on Tuesday, January 3.
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Pictures of Benedict are distributed outside St. Peter's Basilica on Tuesday.
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Nuns arrive at dawn to view Benedict's body on Tuesday.
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The former Pope's body was moved to St. Peter's Basilica on Monday morning, where it was laid out for the faithful to bid farewell, the Vatican said.
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People take pictures of the late Pope on Monday.
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The Pope lies in state on Monday.
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People line up to enter St. Peter's Basilica on Monday.
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Mourners leave St. Peter's Square after paying their respects to Benedict on Monday.

Dignitaries and religious leaders lined the square on Thursday, which can seat approximately 60,000 people, for the ceremony. Prime Minister Petr Fiala of the Czech Republic, was among those in attendance, according to CNN affiliate CNN Prima.

The ceremony was similar to that of a reigning pope but with some modifications. Benedict was named pope emeritus during the funeral, and the language of some prayers was different because he was not the reigning pope when he died.

Francis started leading the mass Thursday morning, during which he gave a homily at about 10 a.m. local time (4 a.m. ET). Members of the crowd later took part in a Communion.

Benedict’s coffin was transported through the Basilica and transferred to the Vatican crypt for the burial, in the first tomb of John Paul II. The tomb was vacated after John Paul II’s body and remains were moved to a chapel inside the Basilica after he became a saint.

As Benedict’s coffin was carried to St. Peter’s Basilica, many members of the crowd could be heard chanting “Santo Subito,” which is a call for the Pope Emeritus to become a saint immediately.

“God’s faithful people, gathered here, now accompanies and entrusts to him the life of the one who was their pastor,” Francis said as he delivered the homily.

“Like the women at the tomb, we too have come with the fragrance of gratitude and the balm of hope, in order to show him once more the love that is undying. We want to do this with the same wisdom, tenderness and devotion that he bestowed upon us over the years. Together, we want to say: ‘Father, into your hands we commend his spirit.’

“Benedict, faithful friend of the Bridegroom, may your joy be complete as you hear his voice, now and forever,” Francis added.

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Pope Francis presided over the funeral ceremonies of former Pope Benedict in St. Peter's Square at the Vatican, January 5, 2023.
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Members of the faithful, including Georg Gänswein (second from right), archbishop of the Curia and longtime private secretary to the late Benedict, are in attendance.

At the time of the burial during the rite, a webbing was placed around the coffin with the seals of the apostolic chamber, the pontifical house and liturgical celebrations. The cypress coffin was placed inside a zinc coffin that is soldered and sealed, and subsequently placed inside a wooden coffin, which was buried, according to Bruni.

The ceremony is expected to end at around 11:15 a.m. local time (5.15 a.m. ET).

High-profile dignitaries including Queen Sofia of Spain and German Chancellor Olaf Scholz are set to attend the funeral, alongside US Ambassador to the Holy See Joe Donelly.

Guglielmo Mangiapane/Reuters
Benedict's coffin was carried through St. Peter's Square.
Guglielmo Mangiapane/Reuters
Cardinals paid tribute to the former pope.

Benedict was elected pope in April 2005 following John Paul II’s death. He was known to be more conservative than his successor, Pope Francis, who has made moves to soften the Vatican’s position on abortion and homosexuality, as well as doing more to deal with the sexual abuse crisis that has engulfed the church in recent years and clouded Benedict’s legacy.

The scroll that was put inside Pope Benedict XVI’s coffin, which is a biography of his life and mentions some of the most important moments of his tenure, recalls that he “firmly” fought against pedophilia.

“He firmly fought against crimes committed by members of the clergy against minors or vulnerable persons, continually calling the Church to conversion, prayer, penance and purification,” the scroll said.

His death prompted tributes from political and religious leaders including US President Joe Biden, British Prime Minister Rishi Sunak and the Dalai Lama.

View this interactive content on CNN.com

About 200,000 mourners, including Italian Prime Minister Giorgia Meloni and President Sergio Mattarella, paid their respects to the former pontiff earlier this week during his lying-in-state in St. Peter’s Basilica.

The public viewing of Benedict finished Wednesday, before an intimate religious rite during which items including coins and medals minted over his tenure and a scroll about the pontificate were placed into his sealed cypress coffin ahead of the funeral.

Meloni paid homage to “enlightened theologian” Pope Emeritus Benedict XVI in a tweet on Thursday.

“Today in St. Peter’s to bid a last farewell to Benedict XVI, Pope Emeritus. Enlightened theologian who leaves us a spiritual and intellectual legacy of faith, trust and hope,” Meloni tweeted after the funeral, which she attended.

“We have the task of always preserving and honoring it and of carrying on its precious teachings,” she added.

The Italian government previously announced on Wednesday that Italian and European flags would be flying at half-staff on public buildings across Italy on Thursday.

CNN’s Delia Gallagher, Valentina di Donato and Sharon Braithwaite reported from Rome. CNN’s Sana Noor Haq reported from London. CNN’s Allegra Goodwin and John Allen contributed reporting.