Diplomat, courtier, and heretic, Juan de Valdes (c.1500-1541) was one of the most famous humanist writers in Renaissance Spain. In this biography, Daniel A. Crews paints a lively portrait of a complex and fascinating figure by focusing on Valdes's service as an imperial courtier and how his employments in Italy - after brushes with the Spanish Inquisition - influenced both Spanish diplomacy and his own religious thought. Twilight of the Renaissance focuses on Valdes's political activities in Charles V's Italian alliance system and negotiations with the papacy, while painting a lively portrait of an intriguing and complex Renaissance figure. Crews examines how Valdes, who was praised by two popes and, the emperor, was also branded a heretic almost immediately after his death. By considering Valdes's spirituality, as well as egotism, this incisive work reveals how the libertine atmosphere of the late Renaissance challenges the saintly Socratic image Valdes fashioned for himself in his writings.