Nazis on the Run: How Hitler's Henchmen Fled Justice
Gerald Steinacher
Oxford University Press, 416pp, £20

The title of Gerald Steinacher's inquiry into how Nazi war criminals escaped from Europe at the end of the Second World War may echo the title of the comedy film Nuns on the Run, but that's as far as the laughs go. This is a scholarly, sober and troubling study, based on interviews with some of the surviving players and exhaustive research in a wide range of archives.

Steinacher demolishes the myth of the Odessa organisation. The idea of a well-heeled groups of ex-SS men devoted to saving their hunted comrades came into existence when the Americans became worried that the Nazis would ship plundered loot abroad to fund a Fourth Reich. This turned out to be fantasy, but the "Nazi hunter" Simon Wiesenthal picked it up and used the notion to explain why so many Nazi criminals had got away. Wiesenthal in turn inspired Frederick Forsyth to write The Odessa File. It was all nonsense. The truth was more prosaic, and all the more shocking.

Even before the war was over, SS men were preparing their escape. They used existing networks and agents to plan the exit routes. Bonds forged in battle or in Allied POW camps provided the basis for mutual aid, but where could they go? The Allies had occupied Germany and were in control of its borders. Yet there was one extraordinary corner of Europe that could have been designed for fleeing Nazis.

South Tyrol was a short step from southern Germany. To reach it entailed crossing two frontiers, but the Austrians did not look too closely at who was passing through, and there were long-established smuggling routes leading into Italy. Jews in flight from the Third Reich had previously used the same safe houses, passes and guides. When Adolf Eichmann set out from Germany in 1950, dressed in South Tyrolean costume, the system "worked like clockwork". He later recalled, "Once it was the Jews - now it was Eichmann."

After crossing the border, Nazi functionaries and SS men could relax. The people of South Tyrol were ethnically German and identified fiercely with German nationalism. In December 1945, the Allies had turned the peninsula over to Italian control, but the Italian security services were grossly inadequate. The government in Rome believed that the best solution to the presence of thousands of refugees and displaced persons was to let them go where they would.

The towns of Merano (Meran, in German) and Bolzano (Bozen) became hubs for the escapees and those aiding them. The Fascist mayor of Termeno (Tramin) was happy to hand out residence certificates that enabled fugitives such as Josef Mengele to get ID cards. The region had been a base for wartime forgers, who kept up the business, now supplying papers to men who needed a new identity. It was hardly a secret; even the local newspaper noted that South Tyrol was an "Eldorado" for former Nazis.

Northern Italy was special for another reason. In the final weeks of the war, Allan Dulles, the representative of the Office of Strategic Services (forerunner of the CIA) in Switzerland, had negotiated the surrender of German forces in that theatre with the SS general Karl Wolff. Dulles thereby ended the fighting earlier than in northern Europe and developed channels of communication with high-ranking SS officers. As Dulles was already looking to rehabilitate Germany as an ally against the rampant Soviet Union, these initial connections would prove doubly useful - to both sides.

Eventually American intelligence organisations would help wanted Nazi war criminals to escape. At first, though, the Germans had to make their own way. They took advantage of the chaos when the fighting stopped and the presence of millions of people, sloshing around the continent without any official papers. Although the United Nations Relief and Rescue Administration and its successor, the International Refugee Organisation, would assist only "genuine refugees", citizens of the defunct Third Reich and ethnic Germans could get emergency travel passes from the International Committee of the Red Cross (ICRC).

For sound humanitarian reasons, the headquarters of the ICRC in Geneva sent thousands of blank passes to the Red Cross offices in Rome and Genoa. Local officials hugely abused the system. The identity checks on applicants were superficial at best. Nazis were able to get affidavits from church organisations that were supposed to be assisting refugees from Catholic countries. However, the Pontificia Commissione di Assistenza (PCA), based in the Vatican under the supervision of the papal secretary of state Giovanni Montini, was interested mainly in helping anti-communists flee the Soviets.

Steinacher provides damning evidence of Vatican complicity. Montini - who in 1963 became Pope Paul VI - permitted Bishop Alois Hudal of Austria, Monsignor Krunoslav Draganovic of Croatia and Father Eduard Dem­öter, a Hungarian, to run aid committees that were used blatantly by fleeing Nazis and Nazi collaborators. In the Diocese of Bressanone (Brixen), Bishop Johannes Baptist Geisler threw open church properties and monasteries to shelter them. In return, many SS men allowed themselves to be rebaptised. Steinacher argues convincingly that this procedure was part of a Vatican strategy to re-Christianise Europe.

American intelligence agents soon joined the clients of the PCA. By mid-1946, they were uncovering "ratlines" and their operatives, in order not to shut them down, but to evacuate men whom they perceived as potential assets. These were former German officers who once ran agents behind Soviet lines or knew Russia well. The beneficiaries included Klaus Barbie, the "Butcher of Lyon", and Walter Rauff, who had pioneered the use of gas vans.

Most of the fugitives aimed for Argentina, which was recruiting technicians and scientists among Germans who wanted to leave Europe. Here, Steinacher draws heavily on the work of Uki Goñi and the Argentinian commission, established in 1997, which researched Nazi activity in the country. He criticises the "one-sided focus on Argentina as a Nazi refuge", but gives little information about other choice destinations such as Syria and Egypt. Nor does he add much about those who reached the US.

The author could also have furnished more context on what was known about the fugitives at the time. The main efflux was under way before the completion of the Nuremberg Trials, with all they revealed. Until the trial of Einsatzgruppen commanders in 1947, few Allied officials had much idea which SS officers were responsible for the mass shooting of Jews in Russia or ghetto clearances. The list of escapees, including Franz Stangl, Eduard Roschmann, Josef Schwammberger and Otto Wächter, is stunning - but how many of them were as notorious then as they became?

Steinacher is undoubtedly correct to see the cold war as critical to American behaviour, but he fails to note that fugitive Nazis in Italy had little to fear from British intelligence, either, though for different reasons. Whitehall was so concerned with stopping European Jews getting to Palestine and Palestinian Jews getting to Europe (to attack British targets) that it had little energy or resources to spare for the likes of Erich Priebke. However, these are minor omissions from a well-written book that is packed with startling information and grubby stories about the moral cost of political exigency.

David Cesarani is a professor of history at Royal Holloway, University of London