(This Sept. 17 story has been corrected to clarify that while the town of Rava-Ruska is now in Ukraine, the site of the Belzec camp is in Poland in paragraph 5)
By Philip Pullella
(Reuters) - Wartime Pope Pius XII knew details about the Nazi attempt to exterminate Jews in the Holocaust as early as 1942, according to a letter found in the Vatican archives that conflicts with the Holy See's official position at the time that the information it had was vague and unverified.
The yellowed, typewritten letter, reproduced in Italy's Corriere della Sera on Sunday, is highly significant because it was discovered by an in-house Vatican archivist and made public with the encouragement of Holy See officials.
The letter, dated Dec. 14, 1942, was written by Father Lother Koenig, a Jesuit who was in the anti-Nazi resistance in Germany, and addressed to the pope's personal secretary at the Vatican, Father Robert Leiber, also a German.
Vatican archivist Giovanni Coco told the Corriere that the importance of the letter was "enormous, a unique case" because it showed the Vatican had information that labour camps were actually death factories.
In the letter, Koenig tells Leiber that sources had confirmed that about 6,000 Poles and Jews a day were being killed in "SS-furnaces" at the Belzec camp in southeastern Poland. The camp was about 20 km (12 miles) northwest of the town of Rava-Ruska, a railway centre that was then also part of German-occupied Poland but is now in western Ukraine.
"The newness and importance of this document derives from a fact: now we have the certainty that the Catholic Church in Germany sent Pius XII exact and detailed news about the crimes that were being perpetrated against the Jews," Coco told the newspaper, whose article was headlined: "Pius XII Knew".
Asked by the Corriere interviewer if the letter showed that Pius knew, Coco said: "Yes, and not only from then."
DOCUMENTS SORTED HAPHAZARDLY
The letter made reference to two other Nazi camps - Auschwitz and Dachau - and suggested that there were other missives between Koenig and Leiber that either have gone missing or have not yet been found.
Supporters of Pius say he worked behind the scenes to help Jews and did not speak out in order to prevent worsening the situation for Catholics in Nazi-occupied Europe. His detractors say he lacked the courage to speak out on information he had despite pleas from Allied powers fighting Germany.
The letter was among documents Coco said were kept in haphazard ways in the Vatican's Secretariat of State and only recently handed over to the central archives where he works.
Suzanne Brown-Fleming, director of International Academic Programs at the U.S. Holocaust Memorial Museum in Washington DC, told Reuters in an email that the release showed that the Vatican was taking seriously Pope Francis' statement that "the Church is not afraid of history" when he ordered the wartime archives opened in 2019.
"There is both a desire for and support for a careful assessment of the documents from a scientific perspective - whether favourable or unfavourable in what the documents reveal," she said.
In an email to Reuters, David Kertzer, Pulitzer Prize-winning author of "The Pope at War", a 2022 book about the Pius years, said Coco was a "top notch, serious scholar", centrally placed in the Vatican to unearth the truth.
Brown-Fleming, Coco and Kertzer will be part of a major conference on Pius and the Holocaust next month at the Pontifical Gregorian sponsored by Catholic and Jewish organisations, the U.S. State Department and Israeli and American Holocaust research groups, among others.
(Reporting by Philip Pullella, Additional reporting by Ludwig Burger in Frankfurt; Editing by Alex Richardson)