ROME -- A Vatican archivist discovered a letter to Pope Pius XII's personal secretary from a Jesuit priest in Germany, who was active in the resistance against the Nazis, reporting that thousands of Poles and Jews were being incinerated daily in a Nazi concentration camp in occupied Poland.
"It is a unique case; it has tremendous value," Giovanni Coco, the archivist, told the Italian newspaper Corriere della Sera in an interview published Sept. 17.
The letter is important, Coco said, because it not only details Nazi crimes at the Belzec extermination camp in 1942, but it refers to other reports and mentions Auschwitz, suggesting that the letter is probably part of much more correspondence between the two priests, said Massimo Franco, the journalist who interviewed the archivist.
"It makes it clear that in reality much more detailed reports about the extermination underway were getting to the Vatican," Franco said in an interview with Radio Radicale Sept. 17.
The other letters have not been found yet, "perhaps they were destroyed or lost," but nonetheless they would have described the Nazis' criminal acts against Catholic clergy, who were part of the resistance, and Jews, he said. The letter Coco discovered had been registered in the archive only in 2019 and was "a bit ruined," Franco added.
The letter is "also important because it makes it clear how much pressure the Nazis were putting on Pope Pius XII and, therefore, how terrorized the Catholic Church in Germany and Poland were that any kind of disclosure could in some way worsen Nazi retaliation against Catholics and Jews," Franco said.
The letter, dated Dec. 14, 1942, was from German Jesuit Father Lothar König, based near Munich, who played an active role in organizing people and initiatives against Hitler's campaigns and in acquiring and sharing information about different camps, including Dachau.
His letter was to German Jesuit Father Robert Leiber, a key and trusted adviser of Pope Pius for decades, starting with the future pope's time as papal nuncio in Munich, then as Vatican secretary of state then as pope from 1939 to 1958.
Father König wrote that it seemed that about 6,000 people, especially Poles and Jews, were killed a day in the "blast furnace" at the Nazi concentration camp in Belzec, Poland. That extermination camp had started its operations in March 1942.
The letter also made reference to the camp at Auschwitz and an "indirect reference to Dachau," Franco said.
"These are some hints that make it clear the so-called 'Final Solution' had already not just begun in 1942, but in some way it is a clear reflection that it was getting (reported) to the Vatican and the pope himself," he said.
It is strongly believed the pope would have received the news in the letter, Franco said, especially since, just 10 days later, Pope Pius made a strongly worded appeal on Christmas Eve.
In that appeal, the pope denounced the fact that hundreds of thousands of people were being "marked down for death or gradual extinction,'' sometimes only by reason of their race; however, he did not explicitly mention the Nazis or Jews by name.
It is expected the letter and future discoveries in the recently-opened Vatican's archives on the pontificate of Pius XII will add to clarifying what the pope knew, what he did and why he did not publicly condemn the atrocities.
Another scholar offered evidence recently found in the Vatican archives that Pope Pius XII knew early on about the Holocaust and used that knowledge to warn the Allies and to save thousands of Jews.
The German historian Michael Feldkamp told Vatican News in 2022 that he found proof that the pope sent a message to U.S. President Franklin D. Roosevelt in March 1942 regarding "the systematic extermination of European Jews" and "warned him that something was happening in Europe in the war zones."
However, Feldkamp said, "these messages were not considered credible by the Americans." Nonetheless, "it is interesting, however, that the president of the United States or his associates in the State Department repeatedly contacted Pius XII for information on individual cases."
"Today we know … that Pius XII was confronted with the persecution of the Jews almost on a daily basis. He had been presented with all the reports and had created his own office within the Second Section of the Secretariat of State, where the staff had to deal exclusively with such matters," he said.
"During World War II, these leaders were in very close contact with Pius XII, reporting to him daily on persecution and mass deportations, as well as on the individual fates of the people who came to them," he said.
"The exciting thing now is that we can estimate that Pius XII personally saved about 15,000 Jews through his own personal efforts: opening monasteries, raising cloisters so that people could be hidden there, and so on. All of this is a huge sensation! The archival findings I have found now in the Vatican show me how accurately Pacelli was informed," the archivist told Vatican News.