Russia and Great Britain were thus in close alliance, and immediately began consideration of a permanent alliance looking toward a regulation of affairs in Europe after the war was ended. The British cabinet took up the question and in 1813 passed a resolution in which occurs the following declaration: “The Treaty of Alliance [between the states which were united against Napoleon] is not to terminate with the war, but is to contain defensive engagements, with mutual obligations to support the Power attacked by France with a certain extent of stipulated succors. The _casus foederis_ is to be an attack by France on the European dominions of any one of the contracting parties.”[4] This provision was kept secret for the time, but it remained the basis of the British policy throughout the negotiations that followed. Castlereagh, in ability and character the greatest statesman of his day, was then at the head of the British cabinet, and it seems certain that he inspired its policy. [4] Phillips, _loc. cit._, 67. He was already suspicious of the position of the tsar in reference to France. That sovereign had in no way relaxed his friendship for the French people. Hating the Bourbons he would have prevented their restoration to the throne, and he had a project for allowing the French to determine whom they would have for king after Napoleon. If he could carry this plan through he would make himself very popular in France and would have a strong position with the ruler whose selection he should thus make possible. To Castlereagh this was nothing but a shrewd piece of policy for laying the foundation of a Franco-Russian alliance which would have overweening influence in Europe, and he set himself against its execution. He was forced to proceed cautiously, however, since Napoleon was not beaten and the aid of the tsar was essential. There is nothing to suggest that Alexander did not entertain his French views in all singleness of purpose. The worst his enemies said of him was that he was a dreamer; but he was not given to a policy of calculation. To thwart Alexander and carry through his own views Castlereagh set himself to “group” the tsar, that is, to draw him into an agreement with other sovereigns in which such a policy was accepted as would serve to deflect the whole group of allies from the direct course which the tsar would have followed if left alone. Early in 1814 a treaty was signed at Chaumont by Great Britain, Austria, Prussia, and Russia in which all the problems then before the allies were taken up. The sixteenth article of the treaty dealt with the point which had caused Castlereagh so much anxiety. It ran: