John Bacon

USA TODAY

Pope Francis canonized into sainthood two 20th Century popes at a Mass on Sunday celebrated before hundreds of thousands of people at the Vatican's St. Peter's Square, lauding his predecessors as "men of courage."

The crowd roared when Pope Francis read the formal proclamation of sainthood for Saint John XXIII and Saint John Paul II. The event drew scores of global leaders as well as Pope Emeritus Benedict XVI, whose decision to step down last year made Francis the leader of the world's 1.1 billion Roman Catholics.

"They lived through the tragic events of that century, but they were not overwhelmed by them," Francis said of the newest saints. "For them, God was more powerful; faith was more powerful — faith in Jesus Christ the Redeemer of man and the Lord of history."

Pope Francis described Saint John XXIII as "the pope of openness to the Spirit" and Saint John Paul II as "the pope of the family." Francis emphasized their faith, saying they were filled with the Holy Spirit and "bore witness before the Church and the world to God's goodness and mercy."

The two new saints "teach us to enter ever more deeply into the mystery of divine mercy," he concluded.

St. Peter's Square was packed for the event. Big-screen TVs were set up in piazzas -- squares — around the city so thousands more could witness the spectacle on a chilly, gray day in the ancient city.

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. He sat with a group of cardinals next to the altar.

Pope John Paul II, the second-longest serving pope in history, led the church from 1978 until his death in 2005. A native of Poland, he was the first non-Italian since Pope Adrian VI, who died in 1523. Polish pilgrims carrying the red and white flags of John Paul's homeland were visible everywhere in the square.

"Four popes in one ceremony is a fantastic thing to see and to be at, because it is history being written in our sight," marveled one of the visiting Poles, David Halfar. "It is wonderful to be a part in this and to live all of this."

John Paul's support for Poland's Solidarity movement is credited with helping to end communism in his native land. He worked to improve relations with other religions, including Jews. He was among the most traveled of popes, visiting more than 120 countries during his rule.

"John Paul was our pope," said Therese Andjoua, 49, a nurse who traveled from Libreville, Gabon, with 300 other pilgrims to attend. "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."

Pope John led the church from 1958 until his death in 1963. He is best known for ordering the Second Vatican Council, a liberalizing effort that actually completed its work two years after John was felled by cancer. He is credited with efforts to modernize the church that included allowing Mass to be celebrated in local languages instead of traditional Latin. Like John Paul, he also pressed for closer ties to other religions: This Council in 1965 issued a landmark document that called for Jewish-Catholic dialogue and rejected the ancient Christian stigma against Jews as killers of Jesus.

Contributing: Associated Press