In a packed St. Peter's Square at the Vatican on Divine Mercy Sunday, Pope Francis officially declared former pontiffs John Paul II and John XXIII as Saints.

"For the honor of the Blessed Trinity, the exaltation of the Catholic faith and the increase of the Christian life, by the authority of our Lord Jesus Christ and of the Holy Apostles Peter and Paul and having sought the counsel of many of our brother Bishops, we declare and define Blessed John XXIII and John Paul II be Saints," Pope Francis exclaimed April 27 as the crowds cheered.

"We enroll them among the Saints, decreeing that they are to be venerated as such by the whole Church. In the name of the Father, and of the Son, and of the Holy Spirit."

Throngs of pilgrims flooded the Vatican on Divine Mercy Sunday to celebrate the highly anticipated canonizations of now-Saints John Paul II and John XXIII.
    
Pope John XXIII was born in Sotto il Monte, a diocese and province of Bergamo, Italy, Nov. 25, 1881 as fourth of 13 children. He was elected Roman Pontiff Oct. 28, 1958.

Known as "Good Pope John," he is most remembered for his historic encyclical "Pacem in Terris," and for his calling of the Second Vatican Council.

He was declared Blessed by Pope John Paul II Sept. 3, 2000, during celebration of the Great Jubilee Year in 2000, and was approved for canonization by Pope Francis last July.

Saint John Paul II is perhaps one of the most well-known pontiffs in recent history, and is most remembered for his charismatic nature, his love of youth and his world travels, along with his role in the fall of communism in Europe during his 27-year papacy.

The cherished Polish Pope died in 2005, marking his 2011 beatification as one of the quickest in recent Church history, and is the first Pope to be beatified by his immediate successor.

In an April 24 message sent to both the Church in Poland and the diocese of Bergamo, Italy, Pope Francis thanked each for the great "gift" of the Saints for the Church and for the world, saying of John Paul II that he is grateful, "as all the members of the people of God, for his untiring service, his spiritual guidance, and for his extraordinary testimony of holiness."

Speaking of Saint John XXIII's historic calling of the Second Vatican Council in order to address a pastoral response to the presence of the Church in the modern world, the Roman Pontiff explained that "the renewal desired from the Second Vatican Council has opened the road."

It is "a special joy that the canonization of Pope Roncalli takes place together with that of Bl. John Paul II," he continued, adding that "this renewal has brought forward in his long pontificate."

Seated alongside the cardinals in attendance for the canonization is retired pontiff Benedict XVI, making this the first Mass in history concelebrated by a Pope and his predecessor.