In July 1936, parts of the Spanish army staged a coup against the republican government. This uprising marked the beginning of a three-year bloody civil war. The book tells the story of German antifascists, Zurich workers, and Swiss intellectuals who gathered in Zurich in August to support republican Spain. It presents new sources on Ludwig Renn, Hans Kahle, and Hans Marchwitza, who had received political asylum in Switzerland in the 1930s and played a significant role in the International Brigades in Spain. This fills an important gap in their biographies. The book also sheds new light on the military trial against Hans Mühlestein and Rudolf Sigg, who were the first Swiss to be convicted in December 1936 for "aiding the journey to Spain" and "participation in hostilities in Spain," respectively.