“He was the greatest gentleman of all time; there will never be another like him.” King of Spain and Holy Roman Emperor, master of the Americas from Mexico to Cuzco, Charles V ruled an empire on which the sun never set, then renounced power at fifty-six. Historian Joseph Pérez tells the story of this towering figure and of his shattered dream: to forge a Europe conscious of its shared identity, above national and ideological divides.