It is customary to think of European art between the First and Second World Wars in the plural—as defined by competing forms of abstraction, divergent realisms, and assorted returns to tradition. The principal goal of Chaos and Classicism: Art in France, Italy, and Germany, 1918–1936 was to assert an underlying unity to the period between the Armistice of 1918 and the Berlin Olympics of 1936. The chaos and mechanized destruction of World War I, the...