After the Reformation, the Dutch Republic emerged as the most religiously tolerant country in seventeenth-century Europe. Benjamin Kaplan examines the reasons behind this phenomenon, focusing on the struggle of Calvinist reformers to realize their theocratic aspirations in the Netherlands, and the fierce opposition offered to them by a large, amorphous group of people known as 'Libertines'. Nowhere was this struggle more intense than in Utrecht, a city at the heart of the Dutch Reformation. The author illuminates the nature of this conflict through a study of the city and people of Utrecht, examining social relations, popular piety, civic culture, and state formation.