Nicolas-Claude Fabri de Peiresc (1580-1637) was, during his lifetime, one of Europe's most famous men. A friend of Pope Urban VIII and Galileo, of Peter-Paul Rubens and Hugo Grotius, of Tommaso Campanella and Marin Mersenne, Peiresc played an important role in the intellectual culture of his time. This book is the first study in English of this extraordinary man, as well as a vivid portrait of his whole circle. Looking through the lens of Peiresc's life, Peter N. Miller brings into focus the early-seventeenth-century world of learning--its people, places, and ideas. Drawing on the extensive Peiresc archive (more than 50,000 pieces of paper), Miller brilliantly evokes the lives of antiquaries, philosophers, theologians, and politicians of Peiresc's day, only some of whom remain known today. He explores the age in which Peiresc's toleration and sociability, his political action and cosmopolitanism, and his serious scholarship without dogmatism were identified as a set of virtues and practices by which to live. Peiresc's notion of scholarship as a moral exercise, the sweep of his interests, and the cross-Continental reach of his intellectual life show with new clarity what it meant to be a man of learning during the decades around 1600.