The new pope, 76-year-old Jorge Bergoglio, who had been the cardinal of Buenos Aires, is the first pontiff from Latin America and the first Jesuit, but he appears to hold views very much in line with his predecessor, Pope Benedict XVI.
Bergoglio, who has chosen the papal name Francis, becomes the 266th to hold the title of spiritual leader of the Catholic Church.
Catholic News Service calls him an accomplished theologian and says Bergoglio has "written books on spirituality and meditation and has been outspoken against abortion and same-sex marriages."
Argentina's La Nacion newspaper says he was born Dec. 17, 1936, in Buenos Aires to Italian parents Mario, a railway worker, and Regina, a housewife.
The newspaper says that when Bergoglio traveled to Rome, he kept a low profile and didn't like to reveal that he was a cardinal.
"That's why he is frequently seen wearing a black overcoat. Also, when he was declared a cardinal, he decided not to buy new clothing. Instead, he ordered the clothing of the previous cardinal be mended to fit him," the newspaper says.
Whispers In The Loggia, a well-respected blog that follows Vatican affairs, says:
"By choosing the name [Francis] of the founder of his community's traditional rivals, the 266th Roman pontiff ... [he] has signaled three things: his desire to be a force of unity in a polarized fold, a heart for the poor, and his intent to 'repair God's house, which has fallen into ruin' ... that is, to rebuild the church."
Thomas X. Noble, a professor of history at Notre Dame University, says the choice of the papal name, after St. Francis of Assisi, who preached in the streets as a pauper, could signal that the new pontiff seeks to be a populist pope.
"This is not a power name, this is not a dogma name," he notes.
The Rev. James Martin, a Jesuit priest who is editor of America magazine, a Catholic weekly, says Bergoglio is "a holy and prayerful man, devoted to the poor and a strong defender of church teaching."
"Remember that as a Jesuit he takes vows of poverty, chastity and obedience, and he will surely be a strong defender of the poor," Martin says.
"He's very much a boots on the ground kind of man," says Donna Bethell, chairwoman of Christendom College in Front Royal, Va. "I think he's going to be a very strong voice for the Church."
Harvey Cox, a professor at Harvard Divinity School, says the choice of a South American cardinal is an acknowledgement that "the growing edge of the Catholic Church is no longer in Europe, it's in the Southern Hemisphere and the non-Western world."
In recent years, he says, Protestants, especially evangelicals, have been making significant inroads in South America, though less so in Argentina than in some other countries.
Cox calls the move a "quantum leap" for the Catholic Church, but speculates that while the conclave "wanted to move outside Western Europe at long last, they didn't want to pin themselves down to a third world pope for the long haul."
The Catholic News Service says Bergoglio, who was archbishop of Buenos Aires until 2012, has a low-key style and is close to the people. He "has had a growing reputation as a very spiritual man with a talent for pastoral leadership serving in a region with the largest number of the world's Catholics."