Joseph Alois Ratzinger was born on April 16, 1927, on the Saturday before Easter — to parents named Josef and Mary — and was baptized the same day in the small Bavarian town of Marktl Am Inn. The baptismal font is now displayed proudly by the town's small museum.
The future pope did not see his birth date as coincidence. "That my life from the beginning was in this way immersed in the Easter mystery has always filled me with gratitude," he said in his German autobiography, "Aus Meinem Leben," published in English as "Milestones: Memoirs 1927-1977."
The family moved often due to his father's work as a policeman, and eventually settled in Traunstein, a town in Germany about 20 miles from the Austrian city of Salzburg.
The church was a constant in small-town Bavarian life, and even as a small boy, Ratzinger was deeply impressed by the ritual of the Roman Catholic Church — candlelight services during Advent in the early morning dark, the Easter service where the Resurrection was announced by suddenly dropping curtains and letting in the light. He entered seminary studies in 1939 as a 12-year-old with "joy and great expectations," according to his memoirs.
But Ratzinger's studies were interrupted in 1943 when he was drafted as an assistant to a Nazi anti-aircraft unit in Munich. Later, he was shipped off to build tank barriers at the Austian-Hungarian border. He wrote that he escaped recruitment by the dreaded SS because he and others said they were training to be priests.
"We were sent out with mockery and verbal abuse," he wrote. "But these insults tasted wonderful because they freed us from the threat of that deceitful 'voluntary service' and all its consequences."
He deserted in April 1945 and returned home to Traunstein. It was a risky move, since deserters were shot or hanged. But the Third Reich was collapsing.
"The Americans finally arrived in our village," he wrote. "Even though our house lacked all comfort, they chose it as their headquarters."
Ratzinger was identified as a deserter and placed in prisoner of war camp near Ulm in southern Germany. He wrote that he could see the spires of the city's cathedral in the distance.
"It was, for me, like a consoling proclamation of the indescribable humaneness of faith," he wrote.
He and his older brother, Georg, were ordained in 1951. Ratzinger taught theology and earned a reputation as a forward-looking prelate and took part in the 1962-65 Second Vatican Council, a major attempt to modernize the faith.
His doctoral dissertation on the medieval theologian St. Bonaventure tried to draw attention to "dangerous relativism" — a message that he has echoed over the years.
He also tried to combine his belief in Christianity's ecumenical message with his views on the special role of Judaism.
"That the Jews are connected with God in a special way and that God does not want that bond to fail is entirely obvious," he wrote in his book, "God and the World," published in 2000. "We wait for the instant in which Israel will say 'yes' to Christ, but we know that it has a special mission in history now."
In 1977, Ratzinger was appointed bishop of Munich and elevated to cardinal three months later by Pope Paul VI.
From November 1981, when he was appointed prefect of the Congregation of the Doctrine of the Faith, he was the Vatican's iron hand.
His interventions are a roll call of flashpoints for the church: the 1987 order stripping American theologian the Rev. Charles Curran of the right to teach because he encouraged dissent; crippling Latin Americans supporting the popular "liberation theology" movement for alleged Marxist leanings; coming down hard on efforts to rewrite Scriptures in gender inclusive language.
He also shows no flexibility on the church's views on priestly celibacy, contraception and the ban on ordinations for women.
In 1986, he denounced rock music as the "vehicle of anti-religion." In 1988, he dismissed anyone who tried to find "feminist" meanings in the Bible. He told American bishops that it was allowable to deny Communion to those who support such "manifest grave sin" as abortion and euthanasia.
He earned unflattering nicknames such as Panzercardinal, God's rottweiler, and the Grand Inquisitor. Cartoonists emphasized his deep-set eyes and Italians lampooned his pronounced German accent.
The name he took on becoming pope — Benedict — draws a connection to Benedict XV, the Italian pontiff from 1914 to 1922 who had the difficult task of providing leadership for Catholic countries on opposite sides of World War I. His declared neutrality, and his repeated protests against weapons like poison gas angered both sides.
Benedict was also known for reaching out to Muslims and for efforts to close the nearly 1,000-year estrangement with Christian Orthodox churches.