From a H-Net review of Claudia Koonz’s The Nazi Conscience:

One of the biggest obstacles to the creation of an antisemitic consensus among both bureaucrats and academics, [Claudia] Koonz found, was that it proved almost impossible in the natural sciences to pin down any verifiable biological differences, to document the racial taxonomy that Nazi ideology insisted must exist. Instead, racial revisionism really took root in the humanities and social sciences. Along with anthropology and ethnology, Koonz notes that “history came into its own as the queen of the racial sciences” (p. 203), generating a flood of bibliographies, archival reports, monographs, and articles to underwrite both ethnic fundamentalism and antisemitism.

Of ethnic fundamentalism, Koonz says:

I use the term “ethnic fundamentalism” to describe deeply anti-liberal collectivism that was the hallmark of public culture in the Third Reich. The term bears an affinity with both religious fundamentalism and ethnic nationalism. Like the former, ethnic fundamenalism claims to defend an ancient spiritual heritage against the corrosive values of industrialized, urban society. Like the latter, ethnic fundamentalism summons its followers to seek vengence for past wrongs and to forge a glorious future cleansed of ethnic aliens. Its leaders, often endowed with charistamtic aura, mobilize followers to participate in a moral universe that is accessible only to those who share a language, religion, culture or homeland.