The part played by Queen Victoria in the conduct of foreign affairs during the early phases of Bismarck's unification of Germany, and more particularly during the crisis of 1866, has been but incompletely revealed in her published correspondence.1 The editors of the Queen's letters, obliged to make a careful selection from abundant manuscript material, could not, from the nature of their task, give a comprehensive account of the Queen's influence on the conduct of diplomatic affairs. Nor has any subsequent historian examined in detail the Queen's tenacious struggle for the success of her German policy. Hardie's study, the only one which covers the subject, is based, on the diplomatic side, exclusively on the Queen's published letters.