New York ? There comes a moment in life when the weight of memory and emotion can lead to action. For Saul Friedlander, that moment arrived when he stumbled upon a misfiled Nazi document in Bonn, Germany, during research for a book on U.S.-German relations before World War II.

Carlos Chavez/Los Angeles Times Photo Saul Friedlander has released his second volume of Holocaust history, The

During 1941, as news of Adolf Hitler’s atrocities began spreading, Pope Pius XII warmly invited the Berlin Opera to perform selections from Wagner at the Vatican, according to a formerly secret telegram that Friedlander found. The faded cable would have riveted any historian investigating papal attitudes toward the Nazis, but it struck a nerve in the young scholar: His parents died at the Auschwitz concentration camp, and he was raised by French Catholics. Fiercely proud of his Jewish roots, his disbelief over Pius XII’s friendly invitation was a transforming moment.

“It shocked me; I was astonished,” said Friedlander, recalling his 1962 discovery. “And I decided then and there that, for me, the right path was to study the history of this event, the Holocaust, so no one would ever forget it. It became my personal fate.”

Today, Friedlander is a pre-eminent Holocaust historian and professor at the University of California, Los Angeles. He recently published the concluding volume in his sprawling chronicle of Hitler’s final solution, “The Years of Extermination: Nazi Germany and the Jews, 1939-1945,” (HarperCollins).

Recently, he received news that has forced him to revisit many of the burning personal questions that have driven his career: Later this year he will receive the prestigious Peace Prize of the German Book Trade at the Frankfurt Book Fair.

Friedlander, 74, views the German honor with mixed emotions. What would his parents have thought? He has spent much of his life documenting Nazi crimes, and his new book may be one of the last Holocaust accounts by a major historian who actually experienced the traumatic events. As a new generation of scholars emerges, Friedlander’s crusade to keep history alive is not just a professional imperative. It’s highly personal.

“For me, the biggest question has always been, how was all this possible?” he said by telephone. “How could such unbelievable atrocities take place in the very heart of Europe, in one of the world’s most advanced countries?”

Not fade away

As historians continue to ponder the Holocaust, Friedlander fears this crucial sense of disbelief may fade with time or disappear in endless academic debate. He voices concern in the introduction to his new book, lamenting that scholars run the risk of “domesticating disbelief” as they try to explain unspeakable horrors. When they parse every detail, “there’s a danger this sense of horror will disappear. Soon you’re accustomed to business-as-usual history. You write about these events with the same detachment you’d use to write about the price of grain.”

To combat this erosion of memory, Friedlander set an ambitious – some would say impossible – goal for his two-volume history (the first book, “The Years of Persecution,” came out in 1997). He resolved that the best way to tell the story was with an “integrated” approach, blending the history of the Nazi perpetrators with the personal stories of victims. He also considered the role of bystanders, some of whom rescued Jews, while others did nothing or aided the Nazis.

The voice of Jewish diarists was prominent: Abraham Lewin, a Warsaw resident in Poland, recorded his dawning awareness of the terror awaiting those deported from the ghetto in 1942: “When people get out of the train, they are beaten viciously. Then they are driven into huge barracks. For five minutes heart-rending screams are heard, then silence. The bodies that are taken out are swollen horribly. Young men from among the prisoners are the gravediggers, and the next day they too are killed.”

Historical context

Born in Prague in 1932, Friedlander fled with his parents to Paris seven years later, after the Germans occupied Czechoslovakia. He survived the war in a French boarding school under an assumed Catholic name, but his parents were captured trying to flee to Switzerland. They perished in Auschwitz. In his 1979 memoir, “When Memory Comes,” he told how a priest revealed to him, at age 15, that his parents were dead.

Reconnecting with his Jewish roots, Friedlander moved to the new state of Israel and fought in the war for independence; he studied in France and Switzerland, received a doctorate in history and taught history at Tel Aviv University. He was invited to teach at UCLA in 1988, filling a newly endowed chair for Holocaust studies.

Throughout his academic career, he has been praised for adopting an even-handed tone, even in his memoir’s more painful moments. When he wrote about Pius XII, he noted that the controversial Wagner performance never took place; he also included a Vatican document challenging the accuracy of the original diplomatic cable.

Beyond his books, Friedlander, who lives in the Laurel Canyon area of Los Angeles, founded the journal History and Memory during his years at UCLA, and received a MacArthur Foundation “genius grant” in 1999.

He also chaired a panel, appointed by the German media giant Bertelsmann, to investigate the company’s wartime connections with Hitler’s Third Reich. The group’s 2002 report prompted the conglomerate to express “sincere regret” for having misrepresented its actions.

Life in Los Angeles has been generally tranquil, Friedlander said, yet there have been jarring reminders that the work of Holocaust inquiry is not complete.

Soon after he began teaching at UCLA, he saw a plane towing an animal-rights banner that read: “Stop Animal Auschwitz.”

“It’s not just the full history of the Holocaust that we have to preserve,” he said. “It’s the very meaning of the word itself, which can be easily misunderstood or taken out of historical context. For me, this is something that must never be forgotten.”