The new saints are a French woman who set up a chapel in a log cabin in the American frontier land and went on to establish a girls' college; a Mexican bishop who risked persecution to educate seminarians; a nun who promoted public schooling for girls in Italy, and an Italian priest who helped the deaf.
"The Church rejoices in the four new saints," Benedict told a crowd of several thousand at the end of the two-hour ceremony. "May their example inspire us and their prayers obtain for us guidance and courage."
Among those celebrating the Mass on the steps of St. Peter's Basilica were prelates based in the U.S. Midwest, including ailing Chicago Cardinal Francis George and five churchmen from Indiana, where Mother Theodore Guerin, who is one of the four new saints, established a college for women, which enrolled its first student in 1841.
George, along with hundreds of alumnae, trustees and students of St. Mary-of-the-Woods College in Indiana, flew to Rome for the ceremony. The cardinal is recovering from bladder cancer surgery he had in late July. The pope and the cardinal embraced at the altar shortly after George recited part of the Mass near Communion time.
Guerin, a frail and sickly woman known for her determination, endured harsh conditions on what was American frontier land in the early 1800s and resisted the objections of a local bishop in pursuing her dream of establishing Catholic education for the pioneers.
Benedict told the crowd that after a long journey by sea and land, Guerin, who was born in Brittany in 1798, and five other French nuns, turned a log cabin into a chapel. By the time of her death in 1856, her order was running schools and orphanages in Indiana, the pope noted.
Young people from the Indiana delegation waved blue scarves when the pope praised Guerin. Many of them wore T-shirts with Guerin's image.
College President Sister Joan Lescinski called Guerin "a perfect example of a strong and courageous woman."
Guerin "is so important to me. She is a friend of us," said Desiree Haines, a 15-year-old student at Guerin High School in Noblesville, Ind.
"She keeps us going, she reminds us everyday that life is hard.
It has been hard for her," said Haines.
The pope also elevated to sainthood Bishop Rafael Guizar Valencia, a missionary who sometimes disguising himself as a street vendor or a musician and risked his life to tend to the wounded during the Mexican revolution.
Faithful in Mexico say that the bishop's body showed remarkably little signs of decay after being removed from burial ground in a cemetery and put on display in the local cathedral some 12 years after his death.
Benedict hailed Guizar Valencia for working tirelessly in "the beloved Mexican nation," even facing persecution, to ensure that seminarians were properly educated "according to the heart of Christ."
Guizar Valencia, who died in 1938, has a controversial modern relative. His grand nephew - Rev. Marcial Maciel Degollado, founder of the Legionaries of Christ religious order - was restricted from public ministry earlier this year by the Vatican, after allegations surfaced that he had sexually abused seminarians.
"We register them in the roll call of the saints and we establish that in all the Church they will be devotedly honored among the saints," the pontiff said, as he read the canonization ritual in Latin.
Benedict, wearing bright green robes and seated under a canopy near the altar, smiled warmly.
Two Italians joined the ranks of sainthood as the Church gives fresh role models to its faithful.
The Rev. Filippo Smaldone, who lived from 1848-1923, pioneered education and other assistance for the deaf and founded an order of nuns, the Congregation of the Salesian Sisters of the Sacred Hearts. The order has convents in Brazil, Moldova, Paraguay and Rwanda.
Rosa Venerini was another social pioneer, advocating education for young girls in Italy. Living from 1656-1728, she founded the Congregation of the Holy Venerini Teachers order of nuns and pushed to establish the first public schools for girls in Italy.
"Their names will be remembered forever," Benedict said of the saints, as he began his homily to the applause of several thousands of faithful in the square.
It was Benedict's first canonization ceremony in nearly a year.
His predecessor, John Paul II, led several canonization and beatification ceremonies yearly, but Benedict has departed from that practice, taking a less visible approach. Ceremonies for beatification, the last formal step before sainthood, are now held in the country where the faithful lived or worked, and the services are led by local prelates.
Members of Guerin's religious order, the Sisters of Providence of St. Mary-of-the-Woods, described the nun's life story as an inspiration for the faithful when the Church was shaken by sexual abuse scandals.
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