In 1912 he went to Munich and called on Wassily Kandinsky, the influential Russian painter and art theorist. Arp was encouraged by him in his researches and exhibited with the Der Blaue Reiter group. Later that year, he took part in a major exhibition in Zürich, along with Henri Matisse, Robert Delaunay and Kandinsky. In Berlin in 1913, he was taken up by Herwarth Walden, the dealer and magazine editor who was at that time one of the most powerful figures in the European avant-garde.