The war turned the Czechs living in France (i.e. the citizens of Austrian-Hungary) into the enemies of France. Formation of Nazdar, a Czech volunteer company within the French foreign legion, became a way out of the situation. It was the painter František Kupka who was the chief of the Paris colony from the beginning of 1915. The sculptor Otto Gutfreund took part in the “rebellion” of Czech volunteers against demeaning conditions in the legion. In 1916, he was sent to a concentration camp. The end of the war reached both artists as being rather sceptical. The war affected their private lives and artistic works, and formed their relation to the French and the domestic Czech environment after 1918. The contribution compares their individual choice in reaction to the makeshift arrangement as well as how they overcame the necessity to be soldiers. The text is based mainly on correspondence between both artists and other archival materials.