Claudia Ann Koonz is an American historian of Nazi Germany. Koonz's critique of the role of women during the Nazi era, from a feminist perspective, has become a subject of much debate and research in itself. She is a recipient of the PEN New England Award, and a National Book Award finalist. Koonz has appeared on the podcasts Holocaust, hosted by University of California Television, and Real Dictators, hosted by Paul McGann. In the months before the 2020 United States presidential election, Koonz wrote about the risks of autocracy in the United States for History News Network and the New School's Public Seminar.

Koonz received a BA in 1962 from the University of Wisconsin, Madison that included two semesters studying at LMU Munich. After a year of traveling overland through Asia, she studied at Columbia University, from which she earned an MA in 1964, before earning a PhD from Rutgers University in 1969.

Claudia Koonz is Peabody Family Professor emerita in the History Department at Duke University. Before coming to Duke in 1988, she taught at College of the Holy Cross in Worcester, Massachusetts, and at Long Island University, Southampton from 1969 to 1971.

Together with Renate Bridenthal, she edited the first anthology of European women’s history, Becoming Visible. She subsequently published two books, Mothers in the Fatherland: Women, the Family and Nazi Politics and The Nazi Conscience, which analyze the sources of ordinary Germans' support for the Nazi Party during Weimar and Nazi Germany. The Nazi Conscience has been translated into Spanish, Japanese, and Russian. Her current book on stereotypes in French media (forthcoming with Duke University Press) is Between Foreign and French: Prominent French Women from Muslim Backgrounds in the Media Spotlight, 1989-2020.

Koonz is best known for documenting the appeal of Nazism to German women and understanding their enthusiasm for the Nazis. Koonz has established that the leaders of German feminist, civic, and religious groups acquiesced to Nazification (Gleichschaltung) that coerced Germans into following Nazi policy. Women in Marxist movements joined with men in operating underground opposition networks. Koonz has noted that female supporters of the Nazis accepted the Nazi division of the sexes into a public sphere for men and a private sphere for women. A reviewer in the New York Times wrote that Mothers in the Fatherland explored the “paradox that the very women who were so protective of their children, so warm, nurturing and giving to their families, could at the same time display extraordinary cruelty.” Koonz has claimed that women involved in resistance activities were more likely to escape notice owing to the "masculine" values of the Third Reich. A mother, for example, could smuggle illegal leaflets through a checkpoint in a pram without arousing suspicion.

Koonz is also known for her claim that two kinds of women asserted themselves in the Third Reich: those, like Gertrud Scholtz-Klink, who gained power over women under their supervision in exchange for subservience to the men who wielded power over them (the authoritarian trade-off) and the women who violated the norms of civilized society, such as camp guards like Ilse Koch. Koonz includes women who were opposed to Nazism 100% as well as "single issue" critics (of, for example, sterilization and euthanasia) but did not protect or protest the deportation of Jews to death camps. Koonz's views have often been pitted against those of Gisela Bock in a battle some have referred to as the Historikerinnenstreit (quarrel among historians of women).

Mothers in the Fatherland integrates archival research into an exploration of “the nature of feminist commitment, complicity in the Holocaust, and the meaning of Germany’s past.” The Nazis promised “emancipation from emancipation,” an appeal that resonated with Germans who feared that male-female equality meant “social and family disintegration.” But Koonz highlights the paradoxes produced by the Third Reich’s dependence on women’s participation (as subordinates, to be sure) in child-bearing, social work, education, surveillance, health care, and compliance with race policy. A reviewer in the New York Times wrote that Koonz dug “deeply and discerningly into a variety of documents, ... to record the mixed results of Nazi efforts at mobilizing women’s groups, secular, Protestant and Catholic” and Jewish women’s efforts to fight against confiscation, ostracism, deportation and murder.

Catherine Stimpson called the contradictory message of Mothers of the Fatherland “painful” because: