The funeral began at 10 am local time with 12 pallbearers in formal dress placing the simple wooden coffin of the pope, marked with a cross and an "M" symbolizing the Virgin Mary, on an ornate rug in front of the outside altar that stood before the doorway to St. Peter's Basilica. When the book of the Gospel was placed on the coffin, the wind lifted the pages and the crowd cheered.
Next 160 cardinals wearing their trademark red vestments and white miters processed into the square and sat in rows that flanked each side of the altar.
Cardinal Joseph Ratzinger of Germany, dean of the College of Cardinals, began the 2 and-a-half hour funeral mass with the confession of sins, a rite that marks the beginning of all Catholic masses.
A close confidant and possible successor to John Paul, Ratzinger's homily traced the life of the pontiff from his days as a factory worker in Nazi-occupied Poland to his final days as the head of the world's 1 billion Catholics.
The usually-composed Ratzinger became audibly emotional when he referenced one of John Paul's last public blessings -- from his studio window on Easter, less than two weeks ago.
"We can be sure that our beloved pope is standing today at the window of the father's house, that he sees us and blesses us," he said to applause, as he pointed up to the third-floor window above the square.
"Today we bury his remains in the earth as a seed of immortality -- our hearts are full of sadness, yet at the same time of joyful hope and profound gratitude," Ratzinger said in Italian.
Throughout the funeral mass the crowd burst into applause and at times shouted the Holy Father's Italian name and their wishes that he be made a saint, "Giovanni Paolo. Giovanni Paolo. Santo. Santo. Santo."
Close to 300,000 mourners filled the square and the Via della Conciliazione boulevard leading toward the Tiber River, many carrying signs and banners from the pope's native Poland and other nations. Prayers read out in a host of languages -- French, Swahili, Portuguese, among others-- reflected the international gathering.
"We just wanted to say goodbye to our father for the last time," said Joanna Zmijewsla, 24, who traveled for 30 hours with her brother from a town near Kielce, Poland, arriving at St. Peter's at 1 a.m. Friday morning.
The funeral ended with the final procession into St. Peter's and the basilica's great bell tolled.
The pope's cypress coffin will be placed inside two others -- one of zinc and one of wood -- before it is interred in the grotto below the church, according to the pontiff's wishes to be buried in "bare ground."
The funeral, attended by four kings, five queens, 14 leaders of other religions and at least 70 prime ministers and presidents including the U.S. delegation headed by President Bush, and including his father, former President George H.W. Bush, and former President Bill Clinton, ranks as one of the largest in modern history.
"It's the largest funeral in the history of the world. I can't get that through my head, but that's what we're witnessing here," Washington's Cardinal Theodore E. McCarrick said.
The 117-voting cardinals will gather in the Sistine Chapel April 18 to begin the secretive process of electing a new pope.