This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book analyses different institutional levels (monarchies, republics, parliaments, municipalities, rural communities) and European territories (France, Italy, the Holy Roman Empire, Scotland, Spain [Crown of Aragon and Crown of Castile]), adopting a comparative perspective and correlating different territorial and social realities between the 16th and 18th centuries. It examines different mechanisms of representation and their scope and limitations prior to the triumph of liberalism. The book analyses the role of such mechanisms in the process of the emergence of the modern state, taking into account the rise of emerging social groups and the processes of oligarchisation of power that took place in Europe during this period. It provides a broad overview and a selection of interconnected case studies, which have rarely been analysed in a comprehensive way.