The Final Act of Congress of Vienna was signed on June 9, 1815. More accurately, because of Napoleon's escape and the consequent battle of Waterloo, the Vienna settlement was completed with the signature of the second Treaty of Paris on November 20s 1815. There is thus no doubt that last year marks the 170th anniversary of the settlement. There is equally no doubt that in many ways 1815 has come to seem very remote. There are no great historical arguments in progress about it, nor does it seem to attract any great interest from the students of international relations, unless their attention is actually drawn to it. So it may be as well to remember that the Vienna settlement has generated much more substantial debate at other times. Very soon after its making, it began to be said that the settlement represented a failed attempt to control, at worst, or suppress, at best, the two doctrines that were to be the political foundation of the 19th century: liberalism and nationalism. By the end of the century this attitude had intensified. In any case, the immense social and political changes which were moulding the modern state structure were beginning to create a new kind of international environment in which the ‘unspoken’ as well as deliberate assumptions of 1815 were less relevant. Approved or not, in practical terms, the settlement remained as a basis for the conduct of international politics until 1914, and thus was the obvious point of departure for discussion about the new settlement which would have to be made when the First World War ended. It is not surprising therefore to find that part of the British preparation for the Paris Peace Conference, which were made by the Political Intelligence Department of the Foreign Office, was a study of the Congress of Vienna by C. K. Webster. It is a somewhat routine piece, and his treatment of the subject was much better based and wider ranging in his monumental study of British foreign policy under Lord Castlereagh. It contained, however, one conclusion which may have had an important effect on the way in which the 1919 settlement was arrived at. Webster said that it had been an error on the part of the allies to have permitted the French to be present at Vienna because of the successful attempt by Talleyrand to insert France into the discussions of the other great powers. It has of course been subsequently felt that one of the cardinal respects in which Vienna was more, sensible than Versailles was precisely in that the French were included and became in effect joint guarantors of the agreement. Whether anything fundamental would have been different had the same been done for the Weimar republic is open to question, but there can be no doubt that the circumstances at the time and afterwards would have been greatly easier had the agenda of post-war international politics not had to include the status of Germany as a first item.