Before the first World War, Cahén moved in German avant-garde art circles, contributing translations of Apollinaire to the Expressionist periodical Der Sturm. As a young critic, he saw a connection between politics and art, suggesting in 1914 that the First World War would be fought over the future of German Expressionism, rather than Belgium's neutrality or the Assassination of Archduke Franz Ferdinand of Austria of June 1914.
