Of all the great questions of Habsburg history, perhaps the greatest is this: What would have been the consequence if Charles V had decided to prioritize differently his dealings with France, the Ottoman Empire, and Christian reformers? It is certain that the House of Habsburg would have proceeded along a different path, but such a truism hardly advances a better understanding of events in the empire, or in Europe more widely, in the sixteenth century. Charles V, as pater ecclesiae and as head of a monarchia universalis, stands astride the traditional and the modern. To him is attributed the last opportunity for Habsburg universal empire, with the long hand of the casa de Austria imprinting Habsburg ambitions on the world.