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Book Summary: The Pope at War – The Secret History of Pius XII, Mussolini, and Hitler

The Pope at War (2022) follows the first years of Eugenio Pacelli’s papacy. Based on documents released by the Vatican in 2020, the book reveals the never-before-told story of the pope’s secret negotiations with Hitler.

Introduction: Get a history lesson about a “great” pope and learn why sometimes silence is the worst crime of all.

History remembers Pope Pius XII in one of two ways: he’s either known as “Hitler’s Pope,” or as a hero to the Jews during World War II.

In 2020, the Vatican released millions of documents by and about Pope Pius XII that had never before been made public. These documents reveal new insights into the man beneath the regalia. They also reveal a new character in the drama of the Axis leaders and their negotiations. This “Nazi Prince” acted as a go-between during a series of secret negotiations between the pope and Hitler.

Book Summary: The Pope at War - The Secret History of Pius XII, Mussolini, and Hitler

What emerges is a more complete understanding of why this pope made the decisions he did. We also get a larger, longer-lasting story – the criminality of silence when you’re in a position of power.

In this summary, we’ll look at the lead-up to Pacelli’s election as pope, the secret negotiations at play, his inaction at the height of wartime, and how everything fell out at the end.

The death of a pope

Sometimes you can see the future coming a mile away. Eugenio Pacelli, who served as secretary of state to Pope Pius XI, left a very distinct impression on those he interacted with. From ambassadors to statesmen to fellow cardinals, people viewed him as a devout and pious man but essentially lacking in will or character. Those opinions should have been a warning sign.

At the beginning of 1939, an aging and ailing Pope Pius XI was going head-to-head with Il Duce, otherwise known as Benito Mussolini. Disgusted with his racial policies and fearful of his connection with Hitler, Pius XI was preparing an encyclical along with a speech. Both would take a hard-line stance against Nazism and the anti-Jewish laws of Italy’s fascist regime.

Unfortunately for the world, on February 10, just days before the speech was to occur, the pope succumbed to his deteriorating health and died. Pacelli was immediately petitioned by representatives of Mussolini to put a stop to the printing and distribution of his predecessor’s speech. Pacelli agreed that it would be best to destroy any existing copies.

The papal conclave which followed saw Eugenio Pacelli elected as pope. He took the name Pius XII after his predecessor even though the two men shared very little in common in terms of personality and character.

Pope Pius XII was determined to be the pope of peace. He wanted to strengthen the church in terms of morality and piety. He was a conservative, in this way, and he viewed the church’s role as independent of nationalism. One day he’d give a speech based on Romans 13:1 which commands Christians to submit to the authority of their governments.

These early days of Pius XII’s papacy were prophetic of what was to come. His immediate withdrawal from his predecessor’s plans along with his focus on peace without regard to justice were early signs of how he’d manage the rest of the war.

While he generally demurred from taking political stances, Pius XII was anxious to participate in brokering peace. One of his first acts was to attempt to bring together a peace meeting. He was given platitudes by Mussolini and Hitler who ultimately rejected his idea, and no such meeting occurred.

But meetings of another sort did occur.

The secret files

When the Vatican first began releasing files on Pius XII in 1965, four Jesuit editors worked to actively expunge all evidence of the pope’s secret negotiations with Hitler. Then, in 2020, the Vatican unsealed millions of those original documents. Through these, we’ve learned of secret meetings between the pope and Hitler’s envoy, the so-called “Nazi Prince.”

The Nazi Prince was a prince named Phillipp von Hessen – one of Hitler’s trusted associates. Married to Princess Mafalda, daughter of the king of Italy, von Hessen had a foot in both nations and was active in helping maintain the relationship between Hitler and the pope.

The first secret meeting resulted in a few changes. The pope brought to the prince’s attention the poor treatment of Catholics in Germany. Not only was there propaganda actively harming the church’s reputation, but Catholic education had also been suppressed. The pope requested the restoration of the church’s ability to operate in Germany.

Hitler would only consider the terms provided the pope made all of his proposals and requests through the secret channel they had built with von Hessen. After this first meeting, Hitler had the German media ease up its “persecution” of the church.

A quick word on that persecution: The Nazi party in Germany had unearthed case after case of sexual abuse of children by Catholic priests. Pope Pius XII ordered records of such cases in Austria to be destroyed. He assured Hitler that the church would deal with cases harshly but that ultimately he hoped Germany would keep quiet about such things.

In the second meeting, von Hessen brought up the topics of racial issues and the German clergy’s outspokenness. He requested the pope continue to remain silent on Germany’s policies towards the Jewish people, and he asked that the pope rein in his people so that they’d stop saying anything against Germany. The pope acquiesced.

By the third meeting, war had begun in earnest and Hitler’s policies toward the German Catholic clergy were considerably different from what he’d promised. Pius XII requested that the church’s freedoms be restored.

Regardless of what had been promised on Hitler’s part, Catholics in Germany continued to suffer.

The war escalates

In situations like this, there’s no such thing as neutrality. By insisting on silence, the pope was effectively choosing a side.

His pattern throughout the beginning of the war was to leave room for the churches in each nation to respond to their individual governments as they saw fit. His motto could easily have been, “It’s best to remain silent.”

When Hitler invaded Poland, the Polish people wrote to the pope begging for him to speak out against this atrocity. The pope remained silent, though he was visibly uncomfortable at the level of brutality happening in the war.

For a moment, Pope Pius XII seemed to have had enough. After Hitler invaded Belgium, Luxembourg, and the Netherlands, the pope was upset and worried. The people of those nations cried out to him for help and he responded by sending the leader of each nation a telegram expressing his heartfelt prayers and regrets. In the telegrams, he affirmed his belief in the injustice of what was happening, albeit in very mild terms. The pope used the Vatican’s newspaper to publish his telegrams as a sort of statement of his policies.

Mussolini was angered by the telegrams and called out the pope directly. Uncomfortable about the backlash, Pope Pius XII actively silenced the Vatican paper and made sure never to publish anything that spoke out against Hitler or Mussolini going forward.

It could be assumed that the pope was a fearful, cowardly man. It could also be assumed that he was a friend of Hitler’s. Both assumptions would be wrong, or at least, incomplete. Everything that has come to light about the pope suggests that he truly wanted to be the pope of peace. He was anti-Semitic, as so many in the church were, but he wasn’t pro-gas-chamber.

The pope’s priority above all was the church. He saw the war as a temporary state and was looking beyond the war at the future of the church. He wrongly assumed that the leaders of the world at that time would be Hitler and Mussolini, so he capitulated to their whims in order to maintain the church’s positive relations with the governments.

In the next section, we’ll get a better idea of how the pope viewed his world by seeing what he prioritized during the war.

The pope’s priorities during the war

While the pope remained silent on the issues of nations falling, soldiers dying, and innocent people being slaughtered, one subject he felt strongly enough to speak on was the issue of purity.

He gave a speech to 4,000 girls all dressed in white about the importance of fighting immorality. Throughout the war years, he continued to encourage young women to dress modestly and remain pure.

Another topic of great importance was the issue of the nation’s entertainment. The pope denounced the government’s lack of intervention and moderation of entertainment programs on television. Young people were being exposed to immoral behavior on variety shows and in movies, and yet the government did nothing.

When he wasn’t crusading on behalf of moral positions like the purity of young girls and the lack of virtue in television, he was busy having a movie made.

To understand the movie, you first have to understand the prophecy of Saint Malachy. Back in the twelfth century, Saint Malachy purportedly had a vision of 112 future popes. He named them all with cryptic phrases. The 106th pope was called the Pastor Angelicus, the angelic shepherd.

This pope was, of course, Pius XII who took to heart his name and entitled the movie about his life Pastor Angelicus.

Of course, the pope was also concerned about war. At the forefront of his mind was a rumor he’d heard that Hitler wanted to eventually do away with the Vatican. The pope asked Mussolini and many others if this was true and they all told him that it wasn’t. Nevertheless, he remained fearful of the possibility.

The tides turn

The landscape of the war began to change after the United States joined the Allies. In his third Christmas speech in 1942, the pope spoke out against the atrocities being committed by the Axis powers. Of course, it was couched in verbose sentences and located all the way on page 24 of his speech, so it didn’t make much of an impact.

Surrounding nations continued to criticize the pope despite his speech, which he found upsetting. For a pope so used to silence, he no doubt considered his speech to have been a hard and strong statement. It wasn’t.

As the Allies began to chip away at Axis gains, the pope found himself in communication with envoys from Britain and America. He made requests that no troops of color be stationed in Rome should there be an Allied occupation. He hoped it would be America rather than Britain that did the occupying because America would eventually leave. He pleaded on behalf of his city that Rome be spared from bombings. These were his concerns.

The Allies promised nothing regarding bombing Rome except that they’d stay away from churches and Vatican city. On the other hand, at one point in the war, Mussolini had hundreds of church bells melted down and turned into artillery.

When the Allies first bombed Rome, they managed to keep all but one church building safe. In the aftermath, the pope visited the damaged basilica and hosted prayers there. He valued being seen in moments like these and shepherding his people during difficult times.

But the one subject he continued to remain silent on was Germany’s policy toward Jewish people. The unsealed files from 2020 show that the pope had confirmation of Germany’s wholesale killing of Jewish people. It wasn’t speculation to him, it was a confirmed fact. And when asked about it by the Allies, the pope kept it all secret.

He was complicit in his silence during Germany’s invasions of sovereign countries. He was complicit in his silence during Hitler’s racial solutions within Germany and Austria. And worse, he was complicit in his silence concerning Rome’s Jewish population.

Best to remain silent

When Italy surrendered conditionally to the Allies, allowing them to land on Italy’s southern tip, Germany rolled in and began occupying Italy to keep the Allies from advancing.

With Germans occupying Rome, Hitler’s policies of rounding up and exterminating Jewish people continued. In Rome, right outside Vatican City, Nazis gathered up over 1,200 people and kept them in an old college building for two days.

During those two days, Pope Pius XII frantically searched the lists and identified over 200 Jewish people who’d converted to Catholicism. Their baptisms confirmed, he was able to have them freed.

For this reason, many hail him as a hero – a real Pastor Angelicus. On the other hand, Jewish families sent letters and cried out to him for help. His reply was that the Vatican was doing everything it could.

Over 1,000 Roman Jewish people were put on a train and sent directly to Auschwitz. The strong were separated from the weak and sent to a labor camp where most of them died. Those deemed too weak were marched directly into the gas chambers. Records suggest that there may have been some survivors of the event – a grand total of 16 survivors.

Throughout all of this, the pope remained silent.

We know the rest of the story of the war. Hitler was systematically beaten back and beaten down by the Allied nations. Mussolini was executed and his body given to the people of Italy who’d never wanted a war to begin with.

The pope, now with the ability to see the lay of the land, became more outspoken. He no longer had a Hitler or a Mussolini to worry about. There were no more consequences to becoming an outspoken leader.

A year after the liberation of Rome, an association of Catholic youths celebrated him as the defender of the church and the one who saved Rome. Some years later, after his death, the church began the process of beatification, or declaring him a saint.

While Pius XII was declared venerable in 2009, Pope Francis put an end to the process of sainthood in 2014 due to there being insufficient miracles attached to his name.


There is a time for silence and there are conditions under which peace should be pursued. But that time and those conditions didn’t exist from 1939 to 1943. Whether it was anti-Semitism, pacifism, or a combination of both that kept Pius XII silent during Hitler’s atrocities, it’s difficult to forgive that silence.

Millions of people died in the war, labor camps, or gas chambers while the leader of the largest, most powerful religious organization on Earth remained silent. It’s impossible not to wonder how things might have been different had he used his power to speak out against what was happening to the Jewish people.

Was Pope Pius XII a hero or a villain? It probably depends on where and when you’re standing – but with hindsight and the evidence of those unsealed documents, it can absolutely be concluded that, whatever his reasons, the pope actively aided in Hitler’s murders by keeping silent when speaking up could have helped.

About the author

David I. Kertzer is the Paul Dupee, Jr., University Professor of Social Science and professor of anthropology and Italian studies at Brown University, where he formerly served as provost. He is the author of twelve previous books, including The Pope and Mussolini, winner of the Pulitzer Prize, and The Kidnapping of Edgardo Mortara, a National Book Award finalist. In 2005 he was elected to membership in the American Academy of Arts and Sciences. Kertzer and his wife, Susan, live in Rhode Island and Maine.


History, Religion, Spirituality, Nonfiction, World War II, Biography, Politics, Italy, Germany, War, Holocaust, European Theater – World War II – Invasion and Occupation, Papacy and Papal History, Vatican City – History, Catholic Church, Memoirs, Leaders and Notable People

Table of Contents

Maps xii
List of Illustrations xvii
Cast of Characters xix
Foreword xxix
Prologue: The Twisted Cross xxxiii

Part 1 War Clouds
Chapter 1 Death of a Pope 3
Chapter 2 The Conclave 18
Chapter 3 Appealing to the Führer 27
Chapter 4 The Peacemaker 41
Chapter 5 “Please do not Talk to Me about Jews” 51
Chapter 6 The Nazi Prince 58
Chapter 7 Saving Face 69
Chapter 8 War Begins 79
Chapter 9 The Prince Returns 86
Chapter 10 A Papal Curse 94
Chapter 11 Man of Steel 101
Chapter 12 A Problematic Visitor 112

Part 2 On the Path to Axis Victory
Chapter 13 An Inopportune Time 129
Chapter 14 An Honorable Death 139
Chapter 15 A Short War 144
Chapter 16 Surveillance 154
Chapter 17 The Feckless Ally 167
Chapter 18 The Greek Fiasco 176
Chapter 19 A New World Order 183
Chapter 20 Hitler to the Rescue 191
Chapter 21 The Crusade 205
Chapter 22 A New Prince 217
Chapter 23 Best to Say Nothing 227

Part 3 Changing Fortunes
Chapter 24 Escaping Blame 247
Chapter 25 Papal Premiere 255
Chapter 26 Disaster Foretold 263
Chapter 27 A Thorny Problem 274
Chapter 28 An Awkward Request 279
Chapter 29 The Good Nazi 294
Chapter 30 Deposing the Duce 303
Chapter 31 Musical Chairs 317
Chapter 32 Betrayal 330

Part 4 The Sky Turned Black
Chapter 22 Fake News 347
Chapter 34 The Pope’s Jews 359
Chapter 35 Baseless Rumors 373
Chapter 36 Treason 388
Chapter 37 A Gratifying Sight 408
Chapter 38 Malevolent Reports 427
Chapter 39 A Gruesome End 441

Epilogue 461
Final Thoughts: The Silence of the Pope 472
Acknowledgments 481
Archival Sources and Abbreviations 485
Notes 489
References 581
Illustration Credits 591
Index 593


When Pope Pius XII died in 1958, his papers were sealed in the Vatican Secret Archives, leaving unanswered questions about what he knew and did during World War II. Those questions have only grown and festered, making Pius XII one of the most controversial popes in Church history, especially now as the Vatican prepares to canonize him.

In 2020, Pius XII’s archives were finally opened, and David I. Kertzer—widely recognized as one of the world’s leading Vatican scholars—has been mining this new material ever since, revealing how the pope came to set aside moral leadership in order to preserve his church’s power.

Based on thousands of never-before-seen documents not only from the Vatican, but from archives in Italy, Germany, France, Britain, and the United States, The Pope at War paints a new, dramatic portrait of what the pope did and did not do as war enveloped the continent and as the Nazis began their systematic mass murder of Europe’s Jews. The book clears away the myths and sheer falsehoods surrounding the pope’s actions from 1939 to 1945, showing why the pope repeatedly bent to the wills of Hitler and Mussolini.

Just as Kertzer’s Pulitzer Prize–winning The Pope and Mussolini became the definitive book on Pope Pius XI and the Fascist regime, The Pope at War is destined to become the most influential account of his successor, Pius XII, and his relations with Mussolini and Hitler. Kertzer shows why no full understanding of the course of World War II is complete without knowledge of the dramatic, behind-the-scenes role played by the pope. “This remarkably researched book is replete with revelations that deserve the adjective ‘explosive,’” says Kevin Madigan, Winn Professor of Ecclesiastical History at Harvard University. “The Pope at War is a masterpiece.”


NEW YORK TIMES BESTSELLER • “The most important book ever written about the Catholic Church and its conduct during World War II.”—Daniel Silva

“Kertzer brings all of his usual detective and narrative skills to [The Pope at War] . . . the most comprehensive account of the Vatican’s relations to the Nazi and fascist regimes before and during the war.”—The Washington Post

Based on newly opened Vatican archives, a groundbreaking, explosive, and riveting book about Pope Pius XII and his actions during World War II, including how he responded to the Holocaust, by the Pulitzer Prize–winning author of The Pope and Mussolini


“A masterly character study of a flawed, tormented leaderand a cautionary tale about the perils of both-sides-ism.”—The New Yorker

“Kertzer brings all of his usual detective and narrative skills to [The Pope at War] . . . the most comprehensive account of the Vatican’s relations to the Nazi and fascist regimes before and during the war.”—The Washington Post

“Definitive.”—The Boston Globe

“Kertzer has spent decades excavating the Vatican’s hidden history . . . [His] new book . . . documents the private decision-making that led Pope Pius XII to stay essentially silent about Hitler’s genocide and argues that the pontiff’s impact on the war is underestimated. And not in a good way.”—The New York Times

“Remarkable.”—Pittsburgh Post-Gazette

“A damning picture of a holy man who chose to remain silent about the mass destruction of European Jewry.”—Haaretz

“A highly readable, a character-driven history well-paced with textured personalities, and a wealth of granular detail . . . [Kertzer] rarely editorializes—the facts are numbingly powerful.”—National Catholic Reporter

“A riveting history and valuable lesson for our time about the perils of neutrality.”—Kirkus Reviews

“Combin[es] extraordinary documentation and elegant writing.”—BookPage

“A captivating account of palace intrigue . . . [his] revelations . . . make sense of a papal tenure often excused away by apologists and, until now, not fully understood by scholars.”—The Forward

“The most authoritative study yet [of Pius XII] . . . a searing indictment.”—HistoryNet

“Fascinating, horrifying . . . a damning portrait.”—Providence Journal

“Thoroughly researched and beautifully narrated.”—Times Literary Supplement

“Kertzer present[s] a highly unflattering evidence of the pope’s role during the Second World War and his silence regarding the Holocaust.”—Ian Kershaw, author of Hitler: A Biography

“With its compelling narrative, interesting and complex characters, strong plot, and beautiful writing, The Pope at War is the best historical nonfiction book I have ever read.”—Alan Lightman, author of Einstein’s Dreams

“With Kertzer’s magnum opus, the book on Pius XII is written, the dispute resolved, the case closed.”—James Carroll, author of Constantine’s Sword

“Brace yourself for a story full of horrors.”—Garry Wills, author of Why I Am a Catholic

“Kertzer has outdone himself and crowned his extraordinary career with this volume on Pope Pius XII.”—Kevin Madigan, Winn Professor of Ecclesiastical History, Harvard University

“A magisterial new study of how the Vatican navigated World War II and why Pope Pius XII stayed silent in the face of the mass murder of Jews.”—Ruth Ben-Ghiat, professor of history and Italian studies, New York University

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Chapter 1: Death of a Pope

Eugenio Pacelli sat in a chair beside the simple brass bed, watching as the once-robust pope, his face shrunken, labored to breathe beneath his oxygen mask. It was late at night, and although Cardinal Pacelli, the Vatican secretary of state, was accustomed to sleeping little, he decided to return to his rooms, two floors below in the vast Apostolic Palace, to get some rest. Awakened at four a.m. with news that the pope’s condition had worsened, he rushed back to the pope’s austere bedroom. Sweat poured down the pope’s pallid face as he gasped for air. The cardinal got down on his knees and asked the dying pope for his blessing.

It was early morning, February 10, 1939. For Pacelli, whom the pope had elevated to the cardinalate and appointed to the church’s most influential position after that of the pontiff himself, it was a scene of great sadness. But there was much to be done, for the pope had also appointed Pacelli to be chamberlain, and it was now his job to ensure that all proceeded as it should until the cardinals could elect a successor.

Pacelli’s relations with the pope had been close but not particularly warm. Their personalities could scarcely have been more different and perhaps this was one reason Pius XI had valued him so highly. The tempestuous pope, prone to say what he thought and often seemingly impervious to the opinions of others, depended on the highly disciplined, diplomatic Pacelli to calm the waters he roiled.

The Vatican secretary of state had found himself caught in the middle. Not only did Mussolini’s and Hitler’s ambassadors complain to him about Pius XI and seek his help, but so did many high-ranking churchmen, worried that the pontiff was becoming reckless in his old age. True to his position and his vows, the cardinal would not fail to carry out the instructions the pope gave him. But he found ways to take the sting out of the pope’s more acerbic remarks about the Italian and German regimes.

Pacelli was a skilled diplomat and, despite a certain natural shyness, took great satisfaction in traveling the globe in a way no secretary of state before him had ever done. During his travels, he enjoyed meeting not only with the church’s ecclesiastical elite but with the politically powerful in secular governments. In the fall of 1936, he became the first Vatican secretary of state to visit the United States, spending two months touring the country, picking up honorary degrees at several Catholic universities, and after thousands of miles crisscrossing the country by air, meeting with the American president.

The following year the cardinal was the guest of honor at the dedication of a new basilica in France, taking a side trip to meet with France’s president and prime minister. A couple of weeks after Hitler visited Rome in May 1938, Pacelli left Italy again, this time going to Budapest, where he was the featured speaker at a Eucharistic Congress. His message everywhere was the same: The world was in crisis. It had turned its back on the cross of Christ. Only by returning to the bosom of the church would it be saved.

While Pius XI was apt to bang his fist on his table and raise his voice in dressing down those foreign envoys whose countries’ actions had displeased him, Pacelli sought to win foreign diplomats over by stressing what they had in common. Insofar as he felt the need to register complaints, he did so in a way that suggested he was speaking more in sorrow than in anger.

Relations between Pius XI and the Führer had begun promisingly enough when Hitler came to power in 1933. Indeed, the pope initially harbored some hopes for him, impressed by the strength of his anti-Communist views. Pacelli, who had spent twelve years as papal nuncio, or ambassador, in Germany and knew the country well, remarked at the time that while Hitler was clearly a remarkably talented agitator, it remained to be seen whether he was “a man of government.”

For his part, Germany’s new leader was eager for the church to end its support of Germany’s Catholic Center Party, the largest non-Marxist party standing in the way of his dictatorship. He made a series of conciliatory gestures, pledging to protect religious education and to guarantee a privileged place for the church in German society. It was amid these assurances that Germany’s bishops fell in line with the new government head, and the Center Party was allowed to die. Their understanding was codified with the signing, in Pacelli’s Vatican office only months after Hitler came to power, of a new concordat between Germany and the Holy See. The deal was a huge boost for Hitler’s credibility not only domestically but also internationally, as the papal nuncio in Berlin himself pointed out a few years later in talking with Germany’s secretary of state: “It does not seem possible to me that Signor Hitler has forgotten that, barely seven months after his arrival in power, when diffidence and hostility surrounded him both internally and externally, the Holy See extended its hand to him, contributing with its great spiritual authority to increasing faith in him and strengthening his prestige.” Characteristically, Mussolini took credit for the agreement, having, he said, given Hitler his successful “recipe” for how to ingratiate himself to the Vatican.

Hitler had long viewed the Duce as his role model. At a Munich rally held only days after Mussolini became Italy’s prime minister in 1922, Hitler, then still one of many extremist claimants for attention in the German political firmament, was introduced as “Germany’s Mussolini.” “It marked,” observed Hitler’s British biographer, Ian Kershaw, “the symbolic moment when Hitler’s followers invented the Führer cult.” Over the next years, as Hitler plotted his rise to power, he kept a bust of Mussolini in his office. “Men like Mussolini are only born once every thousand years,” he remarked after meeting the Duce for the first time in 1934. At the pope’s urging, Mussolini took advantage of that meeting in Venice to offer Hitler his advice: it was best to keep the church happy.

Following his meeting with Hitler, Mussolini wrote to Pius XI, reporting what he had told the Führer. He decided it best not to mention, he confided to his ambassador to the Holy See, “all the idiotic things that Hitler said about Jesus Christ being of the Jewish race, etc.” What was important was that by the end of their conversation, Hitler made clear he did not want a religious war. It would be the first of many times the pope and Cardinal Pacelli would call on the Duce to speak with Hitler on their behalf.

Pius XI’s hopes for the German dictator did not last long. The Nazis soon began replacing Catholic parochial schools with state schools, abolishing Catholic youth groups, and limiting church activities to the purely sacramental. “The pope,” a Vatican police informant in late 1934 reported, “has a strong personal antipathy toward Hitler. If it were not for Pacelli who is trying to bring more balance to the situation, the Secretariat of State would be even less tolerant of him.”

Pacelli too would lose patience with Hitler when, in 1935, he launched show trials of large numbers of Roman Catholic clergy, charged with a variety of sexual and financial crimes. The German bishops urged the pope to act, suggesting he issue an encyclical to protest Hitler’s failure to abide by the terms of the concordat. Although Cardinal Pacelli, worried about antagonizing the Führer, advised against such a public protest, Pius XI went ahead. On March 21, 1937, Palm Sunday, bishops and priests throughout the Reich read the encyclical, Mit brennender Sorge (“With deep anxiety”), to their congregations, a shocking development in a country where any criticism of the Nazi regime risked violent reprisal. Predictably, Hitler was furious not only because of the pope’s attack but by his ability to have the text secretly distributed and then read in churches throughout the Reich.

Hitler’s occupation of Austria in March 1938 and its subsequent annexation into the Third Reich had been an embarrassment for Mussolini, for he had considered Austria as something of an Italian protectorate, a buffer between Italy and the powerful German state. Making matters worse, the Führer had informed him of the invasion only a few hours in advance. The next day Hitler triumphally entered Vienna to the ringing of the city’s church bells, a celebratory touch ordered by the city’s archbishop.

With millions more Catholics now under Hitler’s rule, the pope and his secretary of state looked all the more urgently to Mussolini for help. Five days after Hitler’s entry into Vienna, Cardinal Pacelli wrote Mussolini, thanking him “for Your moderating action with Signor Hitler, Chancellor of the German Reich, and for Your intervention against the continuation of the policy of religious persecution in Germany.”

Hitler’s regard for Mussolini, already considerable, had grown further when, shortly after the Führer’s spring 1938 visit to Italy, the Duce announced his new “racial” policy. Mussolini soon rolled out the first of Italy’s anti-Jewish racial laws, closely resembling those Hitler had put into effect in Germany three years earlier. “After Italy’s new policy regarding the Jewish problem,” Hitler remarked, “the spirit of the Axis is complete.”