This volume argues that language, ethnicity, and identity are defined by the circumstances under which they are created. The foundational chapter by Joshua A. Fishman describes how language, ethnicity, and identity are variable and changeable. The essays in the first part of the Handbook view language and ethnic identity through the lenses of sociolinguistics, psychology, anthropology, politics, and economics. These essays address important topics such as diasporic languages and language and ethnic identity near state borders, as well as the education of Indigenous peoples, language...