‘Bella gerant alii.’ In 1516, by means of traditional dynastic finagling, the house of Habsburg acquired the thrones of Castile and Aragon, or Spain for short: the most bellicose and spectacularly expanding state in Latin Christendom. Henceforth, it seemed, the Habsburgs would no longer be able to leave war to others.

Since concluding Castile’s civil conflicts in the 1470s, the Spanish monarchs had, by force of arms, reconquered parts of French Catalonia, and added other acquisitions to their realms: southern Navarre, the western Canary Islands, Melilla, much of the Caribbean, and the kingdoms of Granada and Naples. For what came to be known as the Spanish monarchy it was the start of the most sustained period of success – measured by the crude, but decisive, standards of victory in the field and expansion on the frontiers – any Western European state had achieved since the Roman Empire.