The controversy over Pius XII hinges on whether he remained too silent during the Holocaust, never publicly condemning the Nazis
Vatican City (AFP) - The unveiling on Monday of Pope Pius XII's archives has been demanded for decades by Jewish groups and historians.
They comprise 120 fonds -- archival documents of the same origin -- and are split into 20,000 units. They add up to millions of pages that could keep historians busy for many years.
Here are four keys to understanding the historic day.
- Published Holocaust archives -
Archives covering World War II have already been widely published by the Vatican. Now researchers will have direct access to an even greater number of documents -- including some of the most sensitive ones.
And none of the pope's post-war papers have previously been released.
In response to swirling controversy over Pius XII, which began almost immediately after his death in 1958, four Jesuit priests capped 16 years of hard work by publishing 11 volumes of archival documents in 1981.
A commission of both Jewish and Catholic historians, established in 1999, decided that still more access was needed to reveal the full truth about the pope's real place in history.
- Prudent expectations -
Suzanne Brown-Fleming, international programmes director at the US Holocaust Memorial Museum in Washington, urged caution.
"It strikes us here at the museum as imprudent to suppose one way or the other what we might find, especially knowing we're talking about 16 million pages and dozens of languages," Brown-Fleming told AFP.
"And the most interesting archival materials are often in hidden folders, or not hidden, that's the wrong word, in unexpected folders. Let's say ones labelled 'miscellaneous'."
Philippe Chenaux, a Pius XII biographer and professor of modern and contemporary Church history at Rome's Pontifical Lateran University, agreed.
"It is not certain that the opening of the Vatican (archives) is likely to bring an end to the controversy over Pius XII's 'silence'," he said in an interview.
"The major contribution of the documents made available concerns the post-war period, or if you prefer, the Cold War, marked by the antagonism between the Christian West and the great Soviet Satan," said Chenaux.
"The end of the 1940s and 1950s have so far been a blind spot in the history of the pontificate."
- Church defends 'just man' -
The Catholic Church has always argued that Pius XII helped rescue several thousand Jews by having them hidden in religious institutions in Rome during the Nazi occupation. It also believes the Pope's refusal to verbally attack the Nazis avoided reprisals against Catholics in Europe.
The process for the beatification of Pius XII began in October 1967. Then-Pope Benedict XVI proclaimed him "venerable" in 2009, the first step towards sainthood on condition that a miracle be recognised -- a decision that spurred an outcry among Jewish organisations.
A year later, Benedict called Pope Pius XII "one of the great righteous, who saved Jews more than anyone else".
"He personally suffered enormously, we know that. He knew he had to speak out, yet the situation forbade him to do so," Benedict noted.
In 2014, Pope Francis said he had "a bit of existential hives" in the face of attacks on Pius XII, "a great defender of the Jews".
- Critics attack his silence -
Pius XII -- a moral voice likely to have been heeded by German Catholics -- is vilified by many historians for never having explicitly condemned the extermination of the Jews by the Nazi regime.
The member of the Roman nobility is also criticised for having remained silent when on October 16, 1943, over a thousand Roman Jews were rounded up in their ghetto not far from the Vatican.
Following the roundup, some Jews were hidden in Catholic institutions, but critics point out that no written document exists to prove that Pius XII was responsible.
Many historians conclude that while this pope may have disapproved of Hitler's anti-Semitism, he was also the product of traditional anti-Jewish Catholic teaching until the Second Vatican Council from 1962 to 1965, which positively transformed Catholic-Jewish relations.
Thus, the Jews were not the priority of this Pope, who was instead concerned about the fate of Catholics and fiercely opposed to communism, they argue.