This chapter introduces the thought of Otto von Gierke. It outlines the philosophical tenets of classical pluralism and its rich vocabulary of group entities. It traces the rise of pluralism in nineteenth-century Germany, through its short golden age in early twentieth-century England, to its eclipse and afterlife following World War I. It argues that classical pluralism offers the most comprehensive and convincing theoretical model on which to regulate the relationship among individual, state and civil society in general, and between English law and British Islam in particular.