Felix A. Theilhaber was a German-Jewish economist and author whose works critically examined the socio-economic conditions of Jewish communities in Germany during the early 20th century. Born in 1884, Theilhaber became an influential voice in discussions surrounding Jewish identity, economic participation, and the impact of societal structures on minority groups. His notable works, including "Der Untergang Der Deutschen Juden: Eine Volkswirtschaftliche Studie," provided a thorough analysis of the economic decline faced by German Jews, highlighting the intersection of economics and anti-Semitism in a rapidly changing society. In addition to his economic studies, Theilhaber contributed to the historical narrative of Jewish participation in World War I with "Jüdische Flieger Im Kriege, Ein Blatt Der Erinnerung," which commemorated Jewish aviators and their contributions to the war effort. His work "Die Schädigung Der Rassedurch Soziales Und Wirtschaftliches Aufsteigen Bewiesen an Den Berliner Juden" further explored the detrimental effects of social mobility on Jewish identity, arguing that economic success did not shield Jewish individuals from societal prejudice. Theilhaber's writings remain significant for their insightful analysis of the challenges faced by Jews in Germany, and they continue to resonate in discussions of minority rights and economic justice.