Accusations that wartime Pope Pius XII was an anti-Semite who turned a blind eye to the Holocaust are part of a "black legend" not supported by historical documents, the author of a new biography says.
The book by Italian journalist Andrea Tornielli - his fourth on Pius - is being published weeks after the Vatican put Pius a step closer to sainthood, a move that angered some Jews.
Some Jews have accused Pius, who reigned from 1939 to 1958, of being indifferent to the Holocaust and not speaking out against Hitler. His supporters consider him a holy man who worked behind the scenes to help Jews throughout Europe.
"This is a black legend that refuses to die. Pius XII has become a lightning rod for all the presumed responsibilities of the Catholic Church in that period," Tornielli said in an interview with Reuters.
Tornielli, a journalist with the newspaper Il Giornale, has called his 650-page biography "Pius XII, Eugenio Pacelli, A Man on the Throne of St Peter." Eugenio Pacelli was Pius' name before he became pope.
In the book, Tornielli cites new documents from the Pacelli family archives showing that as a high school student Eugenio had a close friendship with a Jewish classmate, Guido Mendes.
As Pacelli rose in the Church, he never forgot his Jewish friend, helping the Mendes family when wartime dictator Benito Mussolini enacted the "racial laws" against Jews in 1938, a year before Pacelli was elected pontiff.
Pacelli, then a cardinal and Vatican secretary of state, helped the Mendes family slip into Switzerland, from where they moved to Israel, the book says.
'Another pope may have done it differently'
The Anti-Defamation League has asked Pope Benedict to suspend the sainthood process until the Vatican declassifies its World War Two-era archives "so that the full record of the Pope's actions during the Holocaust may finally be known".
Tornielli's latest book, published by Mondadori, also includes excerpts from letters the future pope wrote to his family in the early 1930s when he was Vatican ambassador in Germany, expressing concern over the rise of Hitler.
"It is impossible to have a calm historical debate about Pius because he has been branded 'the Nazi Pope' and this a clear distortion of history," Tornielli said.
This month, the Vatican's saint-making department voted in favour of a decree recognising Pius' "heroic virtues", a major hurdle in a long process toward sainthood that began in 1967.
If Pope Benedict approves the decree, Pius can move toward beatification, the last step before sainthood.
Diplomatic relations between the Vatican and Israel were briefly tested last month over a photo caption critical of Pius under his picture at a state Holocaust memorial in Israel.
The Vatican maintains Pius did not speak out more forcefully against the Holocaust because he was afraid of provoking Nazi reprisals and worsening the fate of Catholics and Jews.
Supporters say Pius ordered churches and convents in Rome to take in Jews after the Germans occupied the city in 1943. "He believed that was the best way to save lives," Tornielli said.
"The Vatican was surrounded by Italy, a totalitarian state and Hitler's principal ally. The Vatican was spied on," he said.
"Perhaps another pope would have done it differently or spoken out more. The question is: 'what would the result for the victims have been?'" Tornielli said.