‘The glories of the Age of Anne’ – the union of England and Scotland to form ‘this island of Britain’, and its establishment as a European and a global power – were the achievements of two men above all: Queen Anne’s captain-general, John Churchill, the first Duke of Marlborough, and her Lord Treasurer, Sidney, first Earl of Godolphin, of whom it was said that each ‘was the greatest of his kind that hardly any age has afforded’. Their partnership not only embodied the emerging military-fiscal state; it was also a close and lifelong friendship which fully encompassed Marlborough’s beautiful and tempestuous wife Sarah. Tracing the partnership as it proved itself in a succession of victorious summer campaigns in the field and bitterly contested ‘winter campaigns’ at court and in parliament connects and illuminates aspects of a complex period which are often studied in isolation. But was the partnership in the end too successful, too self-contained, too mutually supportive; a dangerous concentration of power and a threat to the queen and the constitution? ‘Rebellion and blood’ were always undercurrents of the glories of the last Stuart reign. A troubled dynasty would come to an end with Queen Anne’s life and a contested succession depended on the outcome of the European war that occupied almost the whole of her reign. This is a story of operatic intensity: of sovereignty and ambition, glory and defeat, but, above all, of love and friendship proved in the hardest use. Its intense human interest and audible voices illuminate a conflicted period which helped to determine the course of modern world.