It was a Saturday — Shabbat — in October 1943. The Nazis had been occupying Rome for a month. An hour before sunrise, they surrounded the Jewish ghetto and began la razzia. The roundup.

Within a few hours, more than a thousand Italian Jews, mostly women and children, had been herded together a few blocks from the walls of Vatican City. As one Nazi ambassador later put it, the Jews were loaded into trucks and taken away “under [the pope’s] very windows.”

Whether that pope witnessed the deportation or not, he said nothing. Only 16 of those Jews would survive.

Sixteen months later, a frail 13-year-old girl in tattered prison stripes collapsed on a train platform. After the Nazis had fled, she wandered from the concentration camp in Poland where she had been imprisoned, trying to get to Krakow, trying to find her family.

But she was starving and could go no farther. She probably would have died there on the cold platform if not for a young man in a long robe who looked to her like a priest. He brought her a warm broth to drink, the first of many things the future pope, Karol Wojtyla, now known to the world as John Paul II, would do to save her life.

Pope Pius XII, who led the Catholic Church from 1939 to 1958, has long been criticized for his public silence during the Holocaust. Critics have argued he also did nothing behind the scenes to stop Nazi atrocities; supporters have claimed he secretly ordered Catholics all over Europe, such as young seminarian Wojtyla, to save thousands of Jews.

Now, the Vatican is opening its archives to researchers, who hope to settle the question for good.

“The Church is not afraid of history,” Pope Francis said last year when he announced the archives would open.

Depending on what they reveal, it could also stop Pius XII’s canonization as a saint. In 2009, he was declared “venerable” by Emeritus Pope Benedict XVI, but the United States Holocaust Memorial Museum and several Jewish groups called for the “wartime materials” about the pope to be released. Benedict XVI initiated the process to prepare more than a million documents for release, which Francis has now completed.

Cardinal Angelo Becciu, who leads the office that investigates possible sainthoods, told The Washington Post last year that historical facts could dictate “whether it is appropriate or not to do a canonization.” Three of the four popes after Pius XII who have died have been canonized.

During World War II, the Vatican maintained a strict neutrality stance. Brown University historian David Kertzer told The Post that while Pius XII “bemoaned the loss of life in a general way,” he “never did speak out directly about the Holocaust.”

In 1963, a German playwright wrote a play depicting the pontiff as a moral coward. Then, in the 1999 book “Hitler’s Pope: The Secret History of Pius XII,” journalist John Cornwell also accused him of being anti-Semitic and of actively collaborating with the Nazis.

Other historians, such as Martin Gilbert, have pushed back against this characterization, claiming Pius XII helped Jews behind the scenes.

Indeed, Gilbert claims that in Rome nearly 5,000 Jews were hidden in Catholic monasteries and convents, including several hundred in the Vatican itself. In northern Italy, thousands more were hidden at the pope’s summer residence; all of this happened at the pope’s direction, according to Gilbert.

Elsewhere, in France and Poland, while some clergy turned against the Jews in their communities, others sheltered and hid them. Vatican officials have said this may have also been at the direction of Pius XII and kept “off the books.”

That may include Wojtyla, who, one biographer claims, helped Jews get false papers as a member of the underground seminary during World War II.

Then there’s Edith Zierer, the young Jewish girl he found at the train station. After feeding and talking with her, Wojtyla carried her to a neighboring town where the trains were working, according to a family account. He boarded a cattle car with her, covered her in his cloak, and rode with her to Krakow. There, she was taken in by other Jews and was separated from her strange protector. She never forgot his name.

Decades later and living in Israel, she learned he was about to become the next pope. They met again at the Vatican in 1998.

Whether the archives will contain evidence linking Pius XII to the good works of other Catholics — exonerating or condemning him — remains to be seen. Kertzer is now in Rome with more than 150 other scholars to begin going through the files. Vatican officials told the Associated Press it will take years, not months or days, for new conclusions to be drawn.

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