The idea of a dialogue – sometimes harmonious, sometimes divisive – between the centre and periphery of the early modern European state stands at the heart of much of John Elliott's historical writing. It is the fulcrum around which his Imperial Spain revolves, and it lies at the core of his analysis of the causes of the revolt of the Catalans in 1640 against the centralizing policies of the Madrid government, directed by the charismatic but insensitive count-duke of Olivares. Elliott subsequently extended the concept of centre versus periphery beyond Spanish shores, notably in ‘Revolution and continuity in early modern Europe’, his inaugural lecture as Professor of History at King's College London, in 1968, which perceived the various revolts of mid-seventeenth-century Europe as essentially conflicts between the loyalties owed to one's patria – representing a province or a principality more often than a nation – and those owed to one's monarch. In his writings on the Americas, too, the relationship between centre and periphery plays a vital role. Elliott's Wiles Lectures of 1969 on The Old World and the New, 1492–1650, the classic statement on the intellectual interchange set in motion by Columbus' voyage, cited the perceptive memorandum of the humanist Hernán Pérez de Oliva to the city of Cordoba in 1524, drawing attention to the way in which the discovery and exploitation of America had affected the relative position of Spain, ‘because formerly we were at the end of the world, and now we are in the middle of it, with an unprecedented change in our fortunes’.