This study focuses on Empires, from an economic historical perspective. In doing so, it relates current debates in international relations (IR) and politics to the vexed legacy of empires in the past. The book includes analyses of the comparative scholarly literature on Empire in Antiquity, and Empire in the Early Modern and Modern Ages, asking the question if the United Sates is an Empire, and if China an emerging Empire. It contributes to the field given its interdisciplinarity, bringing together both historical and IR insights into world systems in times past. In addition it draws out four key points of separateness between pre-modern and modern empires, and emphases specific economic data. Further to that, the book advances the notion of the emergence of “empires from within” in the 21st century, that is nation-states becoming more multi-ethnic while often stepping back from globalization. And finally it offers future scenarios for the evolution of empires in a Schumpeterian post-industrial world.