Erich Heckel (1883-1970) was one of the founders of the artists' group Brücke and thus an important exponent in German Expressionism. The artists' group Brücke existed from 1905 until 1913. The oeuvre of its members such as Ernst Ludwig Kirchner, Karl Schmidt-Rottluff, Erich Heckel is widely known through many exhibitions and publications. Erich Heckel's oeuvre in the years between the two World Wars 1918-1937 deals with the art by Erich Heckel made after the conclusion of Expressionism. The First World War (1914-1918) was a deep cut in life and work of the expressionist artists. The personal development caused by the war experience had a strong influence on Heckel's artistic expression. His painting became more quiet an gentle-lined, the colours became naturalistic and are full of a finely nuanced glowing. Janina Dahlmanns gives a comprehensive account on the biography and life situation of Erich Heckel during the Weimar Republic, followed by a stylistic analysis of his painted oeuvre. The different artistic models and sources of inspiration are being described. The stylistic development of Heckel is also seen in relation to other artistic tendencies of the 1920ies like New Objectivity, Magic Realism and the general return to Naturalism in different European countries. This creatively fertile period in Heckel's life was ended by the rise of the National Socialists in Germany. The fate of Heckel's art work in the campaign of Degenerated Art is concluded.