(CNN) -- St. Francis of Assisi, after whom Pope Francis has taken his name, captures the spirit of many Catholics because church history regards him as the pre-eminent figure passionate about imitating Christ's life.
He is known also as a patron saint of Italy, the founder of the Franciscan order of the Friars Minor, an admirer of nature and a servant to poor and destitute. The brown robe of the Franciscans is iconic.
"Who doesn't know Francis of Assisi, who abandoned everything from wealth and prestige and who became poor himself," Vatican deputy spokesman the Rev. Thomas Rosica said Wednesday, explaining how the saint inspired Pope Francis' name.
"Francis of Assisi is a great, great figure in the church but known especially for connecting with fellow Christians and many people outside the Christian family," Rosica said.
Many popes have written and spoken of St. Francis of Assisi, according to the Vatican's website.
In an encyclical, Pope Pius XI stated that "there has never been anyone in whom the image of Jesus Christ and the evangelical manner of life shone forth more lifelike and strikingly than in St. Francis."
St. Francis "was also rightly spoken of as 'another Jesus Christ,'" Pius XI said.
He was born in Assisi in 1181 or 1182, the son of a rich cloth merchant, and he enjoyed a carefree adolescence and youth, particularly with troubadours.
He went to war at age 20 and was taken prisoner for almost a year. He was released and became seriously ill, which began a major turn in his life.
When he returned to Assisi, a spiritual change commenced, and Francis abandoned his worldliness.
He met with lepers and extended a kiss to one.
In rags, he lived among beggars at St. Peter's Basilica in Rome.
And in one renowned episode, he went to the tattered small church of St. Damian, where Christ on the cross came to life and told him: "Go, Francis, and repair my Church in ruins," recounted Pope Benedict XVI in a 2010 address, according to the Vatican website.
"The ruinous state of the building was a symbol of the dramatic and disquieting situation of the church herself," Benedict said. "At that time the church had a superficial faith which did not shape or transform life, a scarcely zealous clergy, and a chilling of love."
Francis' father questioned his son's generosity and servitude to the poor. While standing before the bishop of Assisi, Francis stripped off his clothes and renounced his paternal inheritance, Benedict said.
Francis lived as a hermit. He went to Rome in 1209 to propose to Pope Innocent III a plan for a new form of Christian life, Benedict said.
The Franciscan order was born.