Luigi Felici / AP

On Monday, 80 years after Pius XII’s election to the papacy, Pope Francis announced that the archives of the controversial wartime pontiff would be opened to scholars next March. The decision follows more than half a century of pressure. Pius XII—a hero of Catholic conservatives, who eagerly await his canonization as a saint, while denounced by his detractors for failing to condemn the Nazis’ genocidal campaign against Europe’s Jews—might well be the most controversial pope in Church history.

Less noticed in initial accounts of the announcement is the fact that Francis’s opening of the Pius XII archives makes available not only the 17 million pages of documents in the central Vatican archives, but many other materials in other Church archives. Not least of these are the archives of the Congregation for the Doctrine of the Faith (formerly known as the Holy Office of the Inquisition) and the central archives of the Jesuit order. They, too, are likely to have much that is new to tell us.

Demands that the Vatican open its archives for the war years began to be heard in 1963, following the premiere in Germany of Rolf Hochhuth’s play, The Deputy. It portrayed a coldhearted Pius XII spurning all pleas to condemn the slaughter of the Jews, concerned only with protecting the institutional interests of the Church. In an effort to respond to the critics, the Holy See commissioned four Jesuits to plow through the archives and publish a selection of documents shedding light on the controversy. The result, over a 16-year period beginning in 1965, was 12 thick volumes containing thousands of documents. Although skeptics suspected the Jesuit editors of selecting out documents unflattering to the Church, the volumes are far from a simple whitewash of this troubled history. To give one example, they show that following Mussolini’s overthrow in 1943, the pope’s Jesuit emissary urgently sought out the new government’s justice minister. His plea: While the Vatican thought that the anti-Semitic racial laws the fascist government had enacted several years earlier had many good qualities and so should be retained, the government should no longer subject baptized Jews to their draconian provisions.

The publication of John Cornwell’s best-seller, Hitler’s Pope, in 1999 gave new life to the controversy. Cornwell reported that he had gotten unauthorized access to portions of the Vatican archives. He argued that in 1933, Eugenio Pacelli, the future Pius XII, helped Hitler end organized Catholic opposition to Nazism in Germany, while Pacelli served as Vatican secretary of state. Later, in Cornwell’s account, not only did Pius do little after his elevation to the papacy to combat the Holocaust as it unfolded, but, following the Allied victory, he shamelessly tried to take credit for having boldly spoken out against Nazism.

The same year that Cornwell’s book was published, the Vatican announced the creation of an unusual interreligious historical commission, composed of three Catholic and three Jewish scholars, tasked with shedding light on the role played by the Vatican as the Holocaust unfolded. After examining the 12 volumes of documents that had earlier been published, its members concluded that they could not draw any adequate historical conclusions without access to the archives themselves. When the Vatican refused to grant their request, the members decided to suspend their work, a decision that generated both embarrassment and polemics.

Meanwhile, the push to declare Pius XII a saint continued. In 2009, Pope Benedict XVI approved a decree proclaiming the heroic virtues of his wartime predecessor, a step toward his beatification. For those in the Church who believe that the liberalizing Second Vatican Council sent the Church down the wrong path, Pius XII, the last pre–Second Vatican Council pope, remains a heroic figure. His partisans have produced a flood of books lambasting those who have questioned his saintly status and, gilding the lily, have made ever more startling claims. Far from spurning requests to act on behalf of Europe’s Jews, they argue, the pope saved hundreds of thousands of Jewish lives. Far from being “Hitler’s pope,” they assert, he played a key role in a plot to assassinate the führer. Recently, partisans of Pius XII have even petitioned to have Yad Vashem, Israel’s memorial to the victims of the Holocaust, honor the pope as a “righteous Gentile.”

Media coverage of the opening of the Pius XII archives has focused almost exclusively on the question of what we will learn about the role played by the pope and the Vatican during the war. Yet many of the most historically significant documents soon to be made available relate not to the war years, but to the immediate postwar period. With much of Europe in ruins, the Vatican was consumed with fears of Communism. Nowhere was this truer than in Italy, where there was good reason to believe that in the wake of Mussolini’s downfall, the Communists might come to power. Pius XII played a major behind-the-scenes role in these fateful years in turning Italians against the Communists. Now, with the opening of the archives, we are likely to learn exactly how he went about it while maintaining a public stance of staying out of politics.

Pope Francis’s election in 2013 gave new hope to those eager to see the Pius XII archives opened. Papal scholars eagerly weighed the latest rumors: How much faith should be placed in the early-2014 report by Rabbi Abraham Skorka, Francis’s Argentinian friend, that the pope wanted to open the archives soon? Was the decision in 2015 to close the Vatican archives for three months for the summer break rather than the customary two made so that the millions of Pius XII documents could be processed more speedily? Each of these reports, and many more, generated earnest speculation among historians camped out in Rome. Yet, amid all these hopeful signs, historians still had their doubts. Didn’t Francis have enough battles to fight with conservatives in the Church without stirring up the raw emotions surrounding Pius XII?

With his March 2 announcement, Francis has put an end to half a century of speculation. The archives will soon be open. But given the large quantity of documents that are to become available for the first time, it will likely be several years before we fully know what revelations they will bring. In the meantime, what has come to be dubbed the “Pius war”—Pius XII, saint or sinner?—will likely only heat up, fed by sporadic reports trickling out from the Vatican’s newly opened archival treasure chest.

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