Language use is a principal means by which we distinguish ourselves and our group from others. In the modern age, language use often divides ethnic groups and nations: Germans are Germans because they speak German; French citizens must accept that Standard French is a central part of their national identity. Sociologists of language consider this equation of personal language use and national identity to be a product of the nationalism which developed in Europe from the eighteenth century on.

Authority and Identity: A Sociolinguistic History of Europe before the Modern Age is the first attempt to take the theoretical and methodological insights of macrosociolinguistics and apply them to the history of Europe before 1500. It analyses the recurrent tensions felt since writing technology first began to be used in Europe some 3,500 years ago between centrifugal and centripetal forces, demonstrating how similar linguistic ecologies can produce different kinds of linguistic authority and identity in individuals and groups due to differing sociolinguistic conditions.