The opening to historians of the archives of the pontificate of Pius XI meant that almost all the peace-time years when Nazis ruled Germany can be seen through papal eyes. This book is learned in the archives and fascinating to read. It does not alter our main picture of the most famous events, like the decision of the Catholic Centre party to vote for Hitler's Enabling Act, the forced withdrawal of the German bishops' condemnation of the Nazi party, the Concordat between Rome and the Reich of July 1933, the drafting of the anti-Nazi encyclical Mit Brennender Sorge of 1937. But it adds many details where every detail is important. The key figure is the Cardinal Secretary of State Pacelli with long expertise in Germany, a steady determination to do nothing that could cause Nazis to persecute German Catholics, and a realism that loud general condemnations were useless and might harm people they were meant to help. He respected Germans for their virtues - hard work, reliability, sense of order and reverence in Church - contrasted with Italians.

There are new materials on why (in 1928) the Vatican refused to alter the phrase in the Good Friday liturgy "perfidious Jews", regarded as anti-Semitic (the villain who opposed the change was the bigot half-Spanish half-British cardinal Merry del Val); and Wolf adds a later history almost till today, on how later Popes, beginning with John XXIII in 1959, altered the language to remove the offence. In the face of popular anti-Semitism, generated partly by the growth of Zionism, partly by Austrian immigration from southern Poland, partly by the Dreyfus case and its effects in French politics, and especially by the violence and hatred stirred through a young Nazi party, several cardinals and other influential churchmen formed a group, the Friends of Israel. In 1928 Rome officially condemned and dispersed the Friends of Israel, mainly on the ground that its ideas proposed a weakness in Catholic tradition. But they were distinguishing the belief that the faith of Judaism is not adequate to the full truth of the Bible, from the rabble demagogy which is prejudice against a people solely because of their race and which is not permitted to Catholics.

The charge against the Papacy, that it could have helped the Jews and failed by silence, became international antipapal propaganda with Rolf Hochhuth's play of 1963. But thirty years earlier, in April 1933, the Vatican was deeply troubled by what was happening when Nazi gangs started maltreating Jews and turning them out of the posts as professors or civil servants. On 26 April 1933 a group of Catholic bishops, led by Berning the Bishop of Osnabrück, gained an interview with four members of the government, Hitler and Göring and von Papen and Bernhard Rust who was then the Prussian Kultusminister. Orsenigo who succeeded Pacelli as nuncio in Berlin gave an account of the meeting which, like all such 'meetings', was a monologue by Hitler. After saying that Germany must be a religious State and that its soldiers were better fighters if they had faith, he distanced himself from Alfred Rosenberg's Myth of the Twentieth Century (1930) which a lot of Nazis seemed to regard as a quasi official ideology designed to replace orthodox Christianity in German culture. He said that through his study of history he knew that in modern times Christianity had not the force it once had, and fought against Liberalism and Socialism and Bolshevism only with intellectual weapons. He turned to the 'Jewish question' and said that he regarded the Jews as vermin and as a danger to Church and state and would do the Church an important service if he treated them as such.

Thus from the end of May 1933 the Vatican knew plainly that Hitler wanted to destroy the Jews. The post brought them heart-rending appeals to help the Jews. We read; and movingly, certain of the letters that came in asking Rome to speak about the persecution of the Jews (among them from Edith Stein), their writers supposing that Rome was more powerful than the cardinals knew to be true. The book not only helps the historian but touches the heart of the reader.

Wolf shows two schools in the Roman Curia proffering advice to the Pope. We know most about the Secretariat of State, because Pacelli was almost daily replying to letters from German bishops or nuncios, and making laconic notes of his consequent interviews with the Pope or with the ambassadors of the powers. We learn more about the person of Pacelli. In early 1924 he decided that nationalism as professed by the Nazis is "probably the most dangerous heresy of our time". When the nuncio in Vienna asked him, as nuncio in Germany, for information about Hitler, he replied that he is a "notorious political agitator". But ex officio as Secretary of State he had a different aim, how do we best seek to protect Catholics in Germany? With the creed of the trained diplomat that to alienate is to make matters worse, never say what might cast oil on the fire. From other Congregations of the Curia, especially the Inquisition, the basic question is of truth and doctrine - when is a State totalitarian and is such a State compatible with Christian moral belief? What is nationalism and does loyalty to one's country share in its error? Ought they to condemn the unchristian errors in Rosenberg's Myth? What about the unchristian errors in Hitler's Mein Kampf? To condemn a book written by a head of State would be a political act but Mein Kampf was written long before its author was a head of state. Here is an interesting description of the arguments inside the Curia.

Pacelli preferred that, if possible, any public procatholic acts in Germany should come from the German bishops. Wolf is therefore able to give portraits of the bishops most trusted by Rome. A good bishop in Pacelli's eyes was devoted to the Roman see; educated in theology and preferably in Rome; not a graduate of a German university; and not pushed into the see by any form of State interference. He thought little therefore of the senior bishop, Cardinal Bertram Prince-bishop of Breslau, whom the Prussian government had forced into that see. Pacelli eyed him as hardly a valid bishop, inadequate in theology and too prone to think that he knew better than Rome what course to pursue. Wolf prints a photograph of an absurd-looking prelate parading before a battalion of the army.

Pacelli knew well Cardinal Faulhaber of Munich and used him as an adviser. He approved of Bishop Sproll of Rottenburg, who later was to have such trouble from the Nazis, partly because Sproll was beloved by the people, and also because he fought hard against women's sport with unsuitable clothing. But his favourite German bishop was Preysing of Berlin. He had a difficulty getting him elected to the see of Eichstätt in 1932, worse difficulty in getting him into the see of Berlin three years later. Wolf describes the Berlin chapter as gnashing their teeth at the election. A strong character but with no sign of protest about the treatment of the Jews.

Wolf's fullest portrait of a German bishop is of Galen of Münster. Preysing thought him an ordinary person who at first had no idea where things were going, was not very intelligent and had a tendency not to want to fight government. By nature he was not a rebel, but loyal and never doubted revealed truth, some said stolid or even lazy. Pacelli believed him a dim preacher. He was priest of the city parish at Münster and it was a surprise when the Bishop of Münster suggested him for the new see of Aachen. When the Bishop of Münster died in 1933, Rome did not put him among the names for the cathedral canons to elect. The canons placed his name third of the three. The nuncio Orsenigo said that he was very devout and loyal to Rome, but some find him arrogant and stuck in his ideas. The canons elected as their bishop a canon of Berlin, who refused for reasons of health. To the vacant place among the candidates Galen was added and in July 1933 elected bishop.

He was tough against Rosenberg's Myth and when Rosenberg came to the Nazi party celebration at Münster in 1935 Galen organized a procession of 20000 people against the new paganism. By 1936 he was protesting against the silence of the bishops lead by Bertram, even protesting to Pacelli. He talked publicly of the rightness of resistance to an illegitimate regime for the sake of human rights. His famous sermons against the secret killing of innocent people were of summer 1941. He was well aware that he risked imprisonment or worse. Martin Bormann wanted him hung from the tower of the parish church in Münster. Pacelli quoted extracts from the sermons when after the war as the next pope he made Galen a cardinal.

But even Galen never felt able to talk openly about the Jews.

Owen Chadwick