The language we use forms an important part of our sense of who we are – of our identity. This book outlines the relationship between our identity as members of groups – ethnic, national, religious and gender – and the language varieties important to each group. What is a language? What is a dialect? Are there such things as language 'rights'? Must every national group have its own unique language? How have languages, large and small, been used to spread religious ideas? Why have particular religious and linguistic 'markers' been so central, singly or in combination, to the ways in which we think about ourselves and others? Using a rich variety of examples, the book highlights the linkages among languages, dialects and identities, with special attention given to religious, ethnic and national allegiances.