Britain's abortive attempt in January 1762 to conciliate Austria and restore the “Old System”—generally known as the Hague Overture—and its subsequent impact on Frederick II of Prussia (then Britain's ally), has never been investigated in detail. Altogether, only two works have ever focused on the episode directly: a brief, but in some ways useful monograph by A. von Ruville, the biographer of Pitt and a later article by W. L. Dorn. Essentially advancing the same interpretation, both authors agree that: Newcastle, by unduly interfering in the Northern Department (held by the Earl of Bute), stands solely responsible for the misleading proposals transmitted to Vienna; and that Bute, lacking a definite policy of his own, submissively followed Newcastle's lead throughout and finally, Kaunitz divulged the story in its most expansive form to Berlin where, as a result, it irreparably damaged Britain's already tarnished reputation. Though forming the nucleus of what is probably the traditional or standard account, endorsed uncritically by most historians up-to-date (among them D. B. Horn, F. Spencer, and R. Browning), these conclusions are highly questionable if not inaccurate, and clearly require substantial revision and modification when reappraised within a wider framework of documentary evidence. Equally, certain important, inter-related aspects have never been studied at all: for instance, the motive forces behind Newcastle's initial formulation of the scheme; the ambivalent role played by Lord Bute; the views and aims of the chosen mediator, Prince Louis of Brunswick; and the deliberations of Baron Knyphausen and Louis Michell, the Prussian envoys in London. This article by utilizing new material from heretofore unexplored sources, aims not only to rectify these and other vital defects, to provide a more coherent, comprehensive outline of events, but also to assess the significance of this episode for Anglo-Prussian relations during a singularly critical period of diplomatic history.