This “well-researched, clear [and] convincing” historical study examines the ideology and politics of Germanization during the WWII occupation of Poland (Nicholas Stargardt, author of The German War). Following the brutal invasion and occupation of Poland, the Nazis moved swiftly to realize one of their key ideological aims: the expansion of German living space. This involved deporting Jews, bringing in German settlers, and establishing an evaluation process that separated Poles from ethnic Germans. As simple as this might have seemed initially, the various parts of the German occupation machinery were soon embroiled in a bitter fight about the essence of Germanness and how to identify a German. In this illuminating study, Gerhard Wolf reveals an astonishing development in which a more inclusive understanding of Germanness based on the notion of Volk won out against an exclusive definition based on Rasse. As Wolf demonstrates, this decision paved the way for turning three million Poles into German citizens. Parallel to the mass deportation and murder of Christian Poles and the genocide of Jewish Poles, the Nazis paradoxically also presided over the largest (forced) assimilation program in German history. Students and scholars of the Second World War, the Holocaust, and Nazism will find new analysis of German imperialism, ethnic cleansing, and genocide in this important book.