Pope Pius xii (Eugenio Pacelli) was by nature a taciturn and solitary man. His part in the Second World War generated debate which is still not ended, but the pope's own silence is easily heard above that considerable and frequently angry noise. It has several aspects, for the pope was silent to the German government when he learned of an army plot to assassinate Hitler in late 1939, and he was discreetly communicative to the Western Allies about what he knew of the plans. Yet already, on becoming pope in 1938, he had also been responsible for suppressing a draft encyclical of his predecessor Pope Pius xi, ‘On the unity of the human race’ (Humani generis unitas); Pius xi would have condemned all racism, with direct reference to Germany and Mussolini's Fascist Italy, and had envisaged ordering Church action against it. As the Holocaust unfolded, and circumstantial and horrific reports reached the Vatican, Pius xii remained silent in public about the Jews. While a variety of Vatican agencies helped thousands of Jews to escape round-ups in Italy, the pope only once nerved himself to make a public statement about their plight, in his Christmas radio broadcast in 1942. Even then, his mention of those ‘put to death or doomed to slow extinction, sometimes merely because of their race or their descent’ failed to put a name to the chief sufferers.

Pius's last near-silence was that of any significant public reflection on his actions after 1945. It lasted through the thirteen years of his pontificate after the war had ended, and it included some deliberate if understandable obfuscation. The first pope to make much use of radio and even, in his last years, television, Pius xii spent his time energetically pronouncing on a vast variety of subjects, some of which might be considered not best calculated to showcase expertise on the part of the Supreme Pontiff, but he showed no inclination to seek any public reconciliation or make any public apology to Jews. His refusal to speak out on this shocked that devout Catholic convert Jacques Maritain, appointed French ambassador to the Holy See after the liberation of France; Maritain frankly regarded Pius’ response to his pleas as evasive, and resigned his diplomatic posting in protest. The pope's most explicit step in that direction, hardly radical, was to order that any translation of the Latin word in the Church's prayer for the Jews which characterised them as perfideles should be ‘unbelieving’ rather than ‘perfidious’. That stands in counterpoint to a memorandum of 1946 passing on to the French bishops a papal instruction that Jewish children baptised during the war should be brought up as Catholics, even if it might keep them from their birth families.

Frank J. Coppa, with a number of distinguished books on the modern papacy to his credit, is well-qualified to provide a balanced summary view of this difficult legacy for those seeking to evaluate Pacelli. There is little theology in his account: the Assumption of Mary does not figure here. He sensibly shows the importance of the fact that Pacelli's ecclesiastical career was shaped through his service to Cardinal Pietro Gasparri and Pope Benedict xv. Benedict was bitterly criticised during the First World War by both combatant blocs for his failure to speak out in their favour, and governments treated with contempt his dogged efforts at diplomacy in the interests of a balanced peace. A sympathetic view of Pacelli's strategy in the Second World War might be that he was only seeking to apply lessons of neutrality and the preservation of lines of communication that he had learned from Benedict's pontificate. Benedict's stock has risen since: there is no sign of that happening to Pius xii, beyond his admirers in the Ultramontane confessional camp. Coppa emphasises the importance of Pius xii's suppression of Humani generis unitas, a matter now the subject of a full-length study by Emma Fattorini, Pio XI, Hitler e Mussolini: la solitudine di un papa (Turin 2007; published in an English translation by Carl Ipsen as Hitler, Mussolini and the Vatican: Pope Pius XI and the speech that was never made). An alert student will derive profit from Coppa's presentation, but will quickly notice that it is scarcely a book, more a rough draft: full of repetitions of text, misspellings, stylistic inelegancies and errors of grammar and syntax. It is difficult to know where blame should chiefly lie, between author or publisher.