"Licence to kill" - this was the message given to the German people during the era of the Third Reich by the two most morally authoritative groups in society, the churches and the universities, Robert Ericksen claims in Complicity in the Holocaust. In confronting just why brutality was legitimised in this way, Ericksen takes us on a tour of German universities and churches from the First World War to the rise of Hitler and beyond.

In spite of its harrowing subject matter, the book is written in a calm, fluent style, easy to read and brimming with careful research, accessible to the general reader. But Ericksen doesn't spare our feelings. His aim is not to shock or provoke anger: that has already been achieved during the six decades or so since the uncovering of the atrocities of the Holocaust. He wants us to understand who perpetrated the Holocaust and how. First, he points out, at some discomfort to the reader, how similar the Germans were to us: they were "rooted in the modern, educated, technologically advanced West". They were not beasts or aliens. Second, he shows how easily overwhelming brutality appeared to arise in the context of 1930s Germany, with its background of economic depression, political disenchantment and frustrated nationalist sentiment. Easily, he claims, due to the endorsement of the moral voice of the nation. His focus is on two institutions that usually enjoy broad respect. "Churches aspire to spiritual and ethical insight. Universities cultivate intellectual acuity."

This book is the accumulation of a lifetime's study and with his erudite scholarship and superb linguistic skills, he surveys the Protestant and then the Roman Catholic churches for their role in the Holocaust. He first notes "widespread enthusiasm for Adolf Hitler among both Protestants and Catholics in 1933". Then he presents an array of damning detail of support in both religious groups for Aryanisation and war, interspersed, he acknowledges, with the occasional protest - for example, Pope Pius XI's complaint to the Nazis. But, as Ericksen points out, this consisted mostly of "ecclesiastical" issues, the Church jockeying for position with the State. His main point is that "when no major Christian institution, from the confessing church to the German Catholic bishops to the Vatican, could find itself willing to condemn Nazi mistreatment of Jews, why would Christians be held back in their participation?" He concludes: "I am not certain ordinary Germans would have participated so willingly and ruthlessly without what appeared to be religious sanction to do so."

From uncovering Church collaboration, Ericksen moves on to assess university academics. In a tour ranging through student activism, Nazi policies of removal of non-Aryans, book burning, hiring policies, curriculum change and governance of the universities, he uncovers a train of Hitlerite policies, but he is at pains to find a single instance of resistance from any university academic (besides the White Rose movement). Personal stories abound, such as that of Karl Brandi, a conservative historian at the University of Gottingen with an aggressive nationalism and "heavy overlay of anti-Semitism", and the philosopher Martin Heidegger, who hailed the authoritarianism of Hitler. All in all, Ericksen shows how the universities provided engineers, administrators, medics and biologists with the skills to enable the mass extermination of 6 million Jews and 5 million other human beings.

Post-war scholarship vindicated many aspects of German society and the image of an oppressed people under the yoke of tyranny arose. In Ericksen's words: "They were only following orders, and they were acting under the extreme duress of a totalitarian state." Ericksen's work opposes that view and contributes to a recent body of scholarship, such as John Cornwell's Hitler's Pope: The Secret History of Pius XII and Hitler's Scientists: Science, War, and the Devil's Pact, that depicts the full extent of various sectors' collaboration with the Third Reich.

This book deserves to be celebrated for its moral courage, lucid prose and splendid craftsmanship - in spite of its complex and emotive content, it reads with beguiling simplicity. Ericksen presents a damning case against the German Church and academy. And by pointing the finger so consistently at educational and moral leaders, he raises questions pertinent to today. Are there evils in 21st-century society that universities and the Church could do more to speak out against?