Pope Francis yesterday proclaimed John Paul II and John XXIII as the Catholic Church's newest saints at a ceremony joined by hundreds of thousands of pilgrims for the two pontiffs who helped shape 20th century history.
"We declare and define as saints the blessed John XXIII and John Paul II," the Catholic leader said in a Latin prayer, as pilgrims and foreign dignitaries massed in St Peter's Square applauded and chanted: "Amen!"
In his homily, Francis praised them as "men of courage" who worked "in renewing and updating the Church".
"They were priests, bishops and popes of the 20th century. They lived through the tragic events of that century but they were not overwhelmed by them.
"For them, God was more powerful," he said.
Pope emeritus Benedict XVI, 87, who last year became the first pontiff to step down since the Middle Ages, made a rare public appearance in his white papal cassock and Francis embraced him before the ceremony.
Francis was co-celebrating the mass with Benedict XVI and hundreds of bishops and cardinals -- the first time that two living popes said mass together.
It was also the first time that two Catholic Church leaders were being declared saints on the same day.
Commentators defined the event as a "four-pope day" and the Vatican said 800,000 people followed the event in Rome, including 500,000 in and around St Peter's Square.
John Paul II was hugely popular but was also a divisive figure who alienated many leftist Catholics during his 27-year reign and has been criticised for turning a blind eye to revelations of child sex crimes by priests.
The charismatic globe-trotting John Paul helped topple Communism in Eastern Europe and John XXIII or "Good Pope John" is best remembered for launching a process of reform of the Catholic Church in the 1960s.
John XXIII helped bring to an end official Catholic prejudice against Jews and has been credited for his pacifying role during the Cold War, including in defusing tensions during the 1962 Cuban Missile Crisis.
The Vatican said 98 foreign delegations were present including former Polish president and Solidarity leader Lech Walesa -- an ally of John Paul II.
The kings of Belgium and Spain also attended, with Queen Sofia of Spain wearing a white dress -- a dress code for the queens of mainly Catholic countries.