This essay takes Georg Simmel’s conceptualization of space as a form of sociation (Vergesellschaftung) in his 1908 masterpiece, Sociology, as a framework for critically re-reading two 19th century classics in the sociology of empire. Alexis de Tocqueville’s Democracy in America (1835/1940) is shown to illustrate Simmel’s understanding of social-spatial boundaries by portraying the cultural and historical geography of America as an ‘optic space’ of racial (in)equality. Similarly, Harriett Martineau’s study of morals and manners in Society in America (1837) exemplifies Simmel’s ideas on social-spatial sensibilities with its attention to how everyday settings serve as a kind of ‘acoustic space&rs...