During the nineteenth-century category of grotesque body was increasingly displaced by the notion of congenital deformity or medical anomaly. Building on this context, the grotesque begins to be understood more in terms as deformity and disability, especially after the First World War, 1914–18. In these terms, the art historian Leah Dickerman has argued that 'The sight of horrendously shattered bodies of veterans returned to the home front became commonplace. The accompanying growth in the prosthetic industry struck contemporaries as creating a race of half-mechanical men and became an important theme in dadaist work.' The poetry of Wilfred Owen displays a poetic and realistic sense of the grotesque horror of war and the human cost of brutal conflict. Poems such as 'Spring Offensive' and 'Greater Love' combined images of beauty with shocking brutality and violence in order to produce a sense of the grotesque clash of opposites. In a similar fashion, Ernst Friedrich (1894–1967), founder of the Berlin Peace Museum, an anarchist and a pacifist, was the author of "War Against War" (1924) which used grotesque photographs of mutilated victims of the First World War in order to campaign for peace.