Crossing Boundaries: Ethnicity, Race, and National Belonging in a Transnational World, edited by Brian D. Behnken and Simon Wendt, explores ethnic and racial nationalism within a transnational and transcultural framework in the long twentieth-century (late nineteenth to early twenty-first century). The contributors to this volume examine how national solidarity and identity--with their vast array of ideological, political, intellectual, social, and ethno-racial qualities--crossed juridical, territorial, and cultural boundaries to become transnational; how they altered the ethnic and racial visions of nation-states throughout the twentieth century; and how they ultimately influenced conceptions of national belonging across the globe. Human beings live in an increasingly interconnected, transnational, global world. National economies are linked worldwide, information can be transmitted around the world in seconds, and borders are more transparent and fluid. In this process of transnational expansion, the very definition of what constitutes a nation and nationalism in many parts of the world has been expanded to include individuals from different countries and, more importantly, members of ethno-racial communities. But crossing boundaries is not a new phenomenon. In fact, transnationalism has a long and sordid history that has not been fully appreciated. Scholars and laypeople interested in national development, ethnic nationalism as well as world history will find Crossing Boundaries indispensable.