By the end of the eighteenth century, politicians in America and France were invoking the natural rights of man to wrest sovereignty away from kings and lay down universal basic entitlements. Exactly how and when did "rights" come to justify such measures? In On the Spirit of Rights, Dan Edelstein answers this question by examining the complex genealogy of the rights regimes enshrined in the American and French Revolutions. With a lively attention to detail, he surveys a sprawling series of debates among rulers, jurists, philosophers, political reformers, writers, and others, who were all engaged in laying the groundwork for our contemporary systems of constitutional governance. Every seemingly new claim about rights turns out to be a variation on a theme, as late medieval notions were subtly repeated and refined to yield the talk of "rights" we recognize today. From the Wars of Religion to the French Declaration of the Rights of Man and of the Citizen to the 1948 Universal Declaration of Human Rights, On the Spirit of Rights is a sweeping tour through centuries of European intellectual history and an essential guide to our ways of thinking about human rights today.