Although many people have come to swallow the caricature of Pope Pius XII as “Hitler’s Pope,” after the malicious smear campaign by John Cornwell, the facts now seem overwhelmingly to reveal the opposite: not only was Pius adamantly opposed to the Führer’s policies; he actively sought to have him assassinated.

A fascinating new book by intelligence expert Mark Riebling, Church of Spies: The Pope’s Secret War Against Hitler, offers a compelling narrative of the actions taken by Pope Pius to stop Hitler from carrying out his campaign of world domination and ethnic cleansing.

Backed by a mass of carefully compiled documentation, Riebling shows that Pius cooperated in a variety of plots, initiated by patriotic, anti-Nazi Germans, to assassinate Hitler and replace the National Socialist regime with a government that would make peace with the West.

The Nazis, in fact, were deeply disturbed by the election of Pius XII in 1939, well aware of Pacelli’s many anti-Nazi statements and actions. They commissioned an assessment of the situation from Albert Hartl, a former Catholic priest, who warned that the Catholic Church would prove a serious threat to the Third Reich.

“The Catholic Church fundamentally claims for itself the right to depose heads of state,” Hartl wrote, “and down to the present time it has also achieved this claim several times.” This statement seemed to embolden disaffected German officers who were seeking assistance to overthrow Hitler.

In 1938, several high-ranking German officers began turning against Hitler, for fear he would lead the country into a devastating war. One of these, General Ludwig Beck, was joined in this endeavor by Admiral Wilhelm Canaris, head of the Abwehr (Germany’s intelligence agency), and his deputy, Colonel Hans Oster.

After the Nazi invasion of Poland in 1939, the German military conspirators sought to reach out to their adversaries, especially the British, to seek aid in overthrowing Hitler. In order to do this, they needed a person who could serve as an intermediary and vouch for their integrity, and so they approached Pius XII, who was highly regarded in Britain.

They asked the pope’s top assistants to ask Pius one critical question: Would he be willing to contact the British government and receive guarantees that it would back the German Resistance if Hitler was overthrown? Pius XII replied that he was willing do so, declaring, “The German Opposition must be heard.”

What followed was a series of gripping events, leading to repeated efforts to depose Hitler, all of which were foiled by unexpected turns, deceit, bombs that failed to detonate, and ones that did go off, only to miss their target. In their quest, the anti-Nazi officers received crucial moral and logistical support from Pius XII, as well as from his closest aides.

This isn’t the first scholarly work to exonerate Pius XII from vicious attacks by his detractors. Rabbi David G. Dalin argued persuasively in his 2005 book, The Myth of Hitler’s Pope: Pope Pius XII And His Secret War Against Nazi Germany, that Pius worked tirelessly to save the Jews from the Nazis. Cornwell’s book, Dalin asserted, not only rewrote history, denied the testimony of Holocaust survivors, and hijacked the Holocaust for unseemly political ends. It also got the story backwards by ignoring the real threat to the Jewish people: the grand mufti of Jerusalem, Hajj Amin al-Husseini. The grand mufti, Dalin wrote, became a steadfast ally of Hitler as well as an active promoter of the Holocaust, calling for the Jews’ extermination.

Dalin contended that the real agenda of Cornwell and his fellow myth-makers was to attack the very idea of the papacy, especially the papacy of the late Pope John Paul II, as well as Christianity and traditional religion as a whole.

A British scholar by the name of Gordon Thomas, a Protestant, has also unearthed extensive material in the Vatican archives that purports to restore Pius XII’s reputation, by revealing the significant part that he played in saving Jewish lives and opposing Nazism.

The Pope’s Jews depicts Pius XII as a somewhat cleverer and more successful Oskar Schindler, saving the lives of countless Jews through ingenious means. Pius gave his blessing to the establishment of safe houses in the Vatican, for example, as well as overseeing a secret operation with code names and fake documents for priests who risked their lives to shelter Jews, some of whom were even made Vatican citizens.

Thomas reports that priests were instructed to issue baptism certificates to hundreds of Jews hidden in Genoa, Rome and elsewhere in Italy. More than 2,000 Hungarian Jews were brought to Rome, after having been given fabricated Vatican documents identifying them as Catholics. Meanwhile, more than 4,000 Jews were hidden in convents and monasteries across Italy.

Hopes for a full rehabilitation of Pope Pius have been stoked during the papacy of Francis, who reportedly is favorable to opening the Vatican archives dealing with the war years. Rabbi Abraham Skorka, a friend of Francis’, said he has discussed the role of Pius XII at length with the Pope, remarking that “I have no doubt that he will move to open the archives.”

For now, we have news of the Pope’s conspiring to assassinate the Führer, which definitely puts to rest any doubts of where his allegiance lay.

Follow Thomas D. Williams on Twitter @tdwilliamsrome