This book examines the evolving concept of "power" in the Polish-Lithuanian Commonwealth (1569–1795), analyzing its theoretical foundations and how the key institutions of power—the king and the Sejm—were perceived. It considers to what extent these ideas dovetailed with European debates or were distinctively Polish-Lithuanian (e.g. the close link between power and freedom). The political system of the Commonwealth, where the nobility participated in governance, shaped both political practice and discourse. This study, examining how power was understood and exercised over two centuries, provides a deeper look at one of Europe’s most distinctive constitutional traditions.