It is part of the accepted wisdom among scholars of the peasantry that Marx got the peasantry “wrong,” as did his pupil Lenin. Yet the fate of overtly peasant parties in Central and Eastern Europe suggests that they did not get the peasants “right” either. This chapter locates that failure in the belief in a single, unified peasant interest. It contrasts the professional sociological opus of the Romanian Dimitrie Gusti with the sociological writings on the peasantry by the Hungarian Ferenc Erdei, who in the interwar years presented Hungarian peasant society in all its complexity. Erdei’s analysis of the interwar peasantry offers far greater differentiation than either the Marxist three-class model or the notion of a unified peasantry. The chapter argues that for Gusti and his followers, a static moral imperative of conformity to the social order—and commitment to a peasant party claiming to represent national identity in the cause of nation-building—appeared as a natural extension of sociology into politics. For Erdei, by contrast, whose sociology was premised on a dynamic interplay of group interests in which peasants formed part of the past, the very idea that a modern national identity could be built on peasant mores was nonsensical—and, indeed, one that he saw failing before his eyes.