This dissertation investigates a significant and under-researched "gray zone" in the study of Nazi Germany and the Holocaust, namely how military authorities under the Third Reich dealt with Nazi racial and social policy within the military. Why did military authorities go to great lengths to justify retaining or reintegrating soldiers with backgrounds that, according to official Nazi policy, defined them as "un-German," such a homosexuals, quarter- and half-Jews, and Roma and Sinti? What does this suggest about the limitations of Nazi social engineering? What connection did this have to the murderousness of the Nazi war of annihilation? At the same time, this study describes how these soldiers recognized military service as an opportunity to "prove" their soldierliness, manliness, and patriotism, which came under suspicion because of their racial backgrounds or sexual behavior.