Focusing on the work of the Hungarian-German sociologist Karl Mannheim (1893-1947), Reinhard Laube examines the genealogy of sociology of knowledge as a self-description of modern society that questions established social premises. Mannheim at first conceives of his perspectivistic observational strategy under the heading of historism, but then as sociology of knowledge. Laube draws on previously untranslated texts to analyze the Hungarian background and Mannheims subsequent participation in the intellectual discourse of the Weimar Republic.