The Vatican estimated that 800,000 people watched the Mass in Rome, with about 500,000 in the square and nearby streets and the rest watching on TV screens that had been set up in piazzas around town.
Polish pilgrims carrying the red and white flags of John Paul's beloved homeland had been among the first to push into the square well before sunrise, as the human chains of neon-vested civil protection workers trying to maintain order finally gave up and let them in.
And while it was supposed to be a canonization for two men, it was clear that the vast majority of people who turned out were there for John Paul.
"John Paul was our pope," said Therese Andjoua, a 49-year-old nurse who traveled from Libreville, Gabon, with some 300 other pilgrims to attend. She sported a traditional African dress bearing the images of both new saints.
"In 1982, he came to Gabon and when he arrived he kissed the ground and told us to 'Get up, go forward and be not afraid,'" she recalled as she rested against a pallet of water bottles. "When we heard he was going to be canonized, we got up."
Kings, queens, presidents and prime ministers from more than 90 countries attended. About 20 Jewish leaders from the U.S., Israel, Italy, Francis' native Argentina and Poland also took part, in a clear sign of their appreciation for the great strides made in Catholic-Jewish relations under John, John Paul and their successors celebrating their sainthood.
Benedict's presence on the altar with them was as remarkable as the historic canonization itself.
Benedict had promised to remain "hidden from the world" after resigning last year, but Francis has coaxed him out of retirement and urged him to take part in the public life of the church.
During the Mass, Benedict sat off to the side of the altar with other cardinals, though he was clearly in a place of honor. He received the Italian president and a steady stream of cardinals. Francis himself embraced Benedict at the beginning and end of the service.
Benedict had arrived in the square on his own to cheers and applause, wearing the same white vestments and white bishops' miter as other cardinals. The only difference was he had a white skullcap on rather than red.
Monika Scislowska contributed from Krakow, Poland and Jim Gomez and Rene Casibang contributed from Manila, Philippines.
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