This thesis studies the professional activities of the German architects in the first half of the 20th Century who have worked as expatriate architects in the newly founded Turkish Republic before and after their arrival in Turkey. The aim of the thesis is to elucidate the effects and interactions of environmental and personal factors which impacted the architectural approaches of the German architects in the Turkish context. Due to the extensive emigration movement from Germany caused by the National Socialist Government after 1933, Mid-European Modern Architecture has detached from its original context and spread throughout the world. The relocation of experienced architects to a new geographical setting, in this case the newly founded Turkish Republic, has provided means for novel experiences and applications. How these architects diversified and progressed under the prevailing multidimensional conditions have been discussed in the light of the unique opportunities and restrictions specific to the Turkish context. The first chapter of the thesis is introductory; the second chapter depicts the architectural milieu in Germany at the beginning of the 20th century and the activities of the German architects who have later come to Turkey. The third and fourth chapters investigate the professional careers of the German architects with emphasis given to the evolution observed in their architectural approaches specifically in the reformist attitudes they introduced to education, and in their architectural designs for the Turkish context. The fifth chapter is the conclusion. Keywords: Exile German Architects, Architecture in Turkey in the Early Republican Period, Bruno Taut, Paul Bonatz, Margarete Schütte-Lihotzky, Hans Poelzig, Wilhelm Schütte, Martin Elsaesser, Robert Vorhölzer