This dissertation investigates the National Socialist mobilization of ethnic German ("Donauschwaben") children and youth in two multiethnic, post-Habsburg borderland territories: the Western Banat and the Batschka. Weaving together archival materials, the contemporary press, and original oral history interviews, it traces the evolution of boys' and girls' extra-curricular youth organizations from the Habsburg Empire's 1918 collapse to the ethnic Germans' 1944 "expulsion" from the region. Focusing initially on the interwar period, the dissertation shows how Yugoslavia's ethnic German educational activists quickly framed their demands on national terms. From the 1920s onwards, secular and religious authorities thereby attracted Germany's attention and aid, giving rise to a "nationalization" of local concerns and a politicization of youth. Curricular frustrations, however, spurred extra-curricular solutions: from the 1930s, Donauschwaben youth became a bone of contention between Catholic, Protestant, pro- Reich, anti-Reich, and Yugoslavist youth organizations, each of which promulgated its own visions of "Germanness." Turning to the years between 1941 and 1944— when the Batschka became Hungarian-occupied, and the Western Banat a semi-autonomous, Reich-occupied territory under ethnic German administration— this dissertation deploys a comparative and multiscalar approach in order to explore the experiences of Donauschwaben children and youth under divergent occupational regimes. In the Banat, the curricular, extracurricular, and military domains meshed to coerce all ethnic German youth into the pro- Nazi "Deutsche Jugend," extinguishing any non-Nazi "national" alternatives; in the Batschka, Hungarian nationalization projects, Catholic activism, and the Third Reich's imperial ambitions continued to compete over the Donauschwaben's loyalty, shattering communities over diverse conceptions of "Germanness." In both regions, the majority of youth ultimately joined National Socialist organizations, thus becoming agents of their own, and their peers', nationalization, actors in local inter- and intra-ethnic conflict, and soldiers in Nazi Germany's devastating military campaigns.