Analysis is provided of the roots of sociology and its links with historical optimism. Particular focus is placed by such a sociology upon the origins of modernity and problems of urban disorder. Sociology's golden age was in the immediate postwar period. But since the 1960s, ‘globalization’, the sciences of complexity and cultural studies have transformed the context for sociology (especially transforming the so-called ‘two cultures’). The article concludes with some wide-ranging recommendations as to how sociology should be developed into a re-unified, historical social science on a truly global scale.