As a documentary filmmaker, Steven Pressman avoids asking historians “what-if” questions, since they prefer dealing with known facts. Still, with his new film “Holy Silence,” it’s hard not to ponder how different things might have been for Europe’s Jews if not for a few twists of fate.

Twistiest of all, on the eve of World War II, an ailing Pope Pius XI seemed ready to issue an encyclical condemning antisemitism and, by implication, Germany’s bent toward genocide. He died in February 1939, and his successor, Eugenio Pacelli (known as Pius XII), scrapped the whole idea.

What if Pius XI had lived and issued his decree? Might he have helped save the Jews?

“We will never know what might have happened,” said Pressman, who lives in San Francisco and completed his documentary as a filmmaker-in-residence at the Jewish Film Institute. “Nobody is going to predict that had Pius XI lived and had his encyclical been issued, that somehow the Holocaust would not have happened. But who knows where it might have had an influence?”

Featuring interviews and rare archival footage, some of it curated by the U.S. Holocaust Memorial Museum in Washington, D.C., “Holy Silence” makes its broadcast premiere on KQED and other PBS stations on Nov. 8, the anniversary of the eve of Kristallnacht.

The film explores the commonly held belief that Pius XII did too little to stop Europe’s descent into fascism during the 1930s and 1940s. Pressman also wanted to introduce viewers to little-known American players who loomed large in the Vatican’s role during the war.

As the title implies, “Holy Silence” suggests that the Vatican under Pius XII was indeed guilty of neglect in the face of unspeakable moral horror. Yet, Pressman says, Pius XII was more complex than many realize.

“I wanted to focus on this notion of silence,” he said. “I fully understand and accept that people can come to the conclusion that silence equals complicity. I don’t think [Pius XII] was evil or enamored of Hitler at all. I think he was probably horrified by what was going on. But he was the product of a church that had a 2,000-year history of not loving the Jewish people, and he was not able to rise above that.”

The film starts in the early 1920s with the emergence of Italian dictator Benito Mussolini, a man who “didn’t have a religious bone in his body,” Pressman said. The Vatican under Pius XI forged a working relationship with Mussolini, one that grew more complicated with the rise of Hitler’s Germany.

That led to the infamous Concordat, a 1933 agreement between the Vatican and Germany that ostensibly protected the church’s activities in Germany but had the effect of muting the Vatican’s objection to Nazi outrages. As secretary of state, Pacelli negotiated that pact, a sign of timidness and self-interest to come.

In 1938, a year before his death, Pius XI had an epiphany. He enlisted a progressive American priest, John LaFarge, who served in poor black parishes and wrote about racial injustice, to draft an encyclical specifically condemning antisemitism. With Catholics considering the pope infallible, such a decree might have sparked stronger resistance to Hitler’s budding genocide.

After I made the first film, I vowed I did not want to make another Holocaust film.

It was not to be. No action was taken on the encyclical. Pius XI died, reportedly with a copy of LaFarge’s draft on his desk. The next pope, Pius XII, ordered all drafts destroyed and the notion of the encyclical forgotten. LaFarge, who lived long enough to attend the March on Washington in 1963, never mentioned it again.

“He was a loyal, obedient Catholic priest,” said Pressman, “and once Pius XII made it clear this [encyclical] would never happen, [LaFarge] would have taken this as a sign it did not happen. The only reason the episode ended up coming to light is that after he died, some of his Jesuit colleagues were going through his papers and they found a copy of his draft.”

The rest is history, and as the film details, Pius XII and his church rode out the war while 6 million Jews perished. History is replete with stories of brave priests and nuns across Europe who hid Jews during the war. But as Catholic author Suzanne Brown-Fleming wonders aloud in the film, “Why did it fail to be a church of love and mercy?”

“Holy Silence” isn’t Pressman’s first cinematic take on the Holocaust. In 2013, the Los Angeles native directed “50 Children: The Rescue Mission of Mr. and Mrs. Kraus,” a documentary that premiered on HBO and was nominated for an Emmy. The film told the story of his late wife’s grandparents, who had traveled from Philadelphia to Nazi Germany in 1939 to save several dozen Jewish children before the walls closed in.

“After I made the first film, I vowed I did not want to make another Holocaust film,” Pressman recalled. “I had been immersed in [‘50 Children’], wrote a book about the same story and was ready to move on. But the more I thought about [the story of Pius XII], the more I thought there was something there.”

Pius XII died in 1958. In the years since, the Catholic Church has sought to reconcile with the Jewish people through its Nostra Aetate declaration of 1965, which officially absolved Jews for the death of Jesus and opened the door to interfaith dialogue with succeeding popes. But historians will have a chance to revisit the troubling war years, as this year the Vatican released 16 million pages of archived documents from the Pius XII era. It will take scholars years to analyze them.

Meanwhile, Pressman hopes his film will shed light on a dark moment in the history of Europe, the church and the Jews.

“Do we need more Holocaust films?” he asked rhetorically. “We need them when they allow us to glimpse some aspect of the Holocaust that maybe we haven’t focused on all that much before, to look at both issues and personalities they might not have known about.”