Denmark did not give way; the help from England, on which they had reckoned, was not forthcoming; the fatal day passed; the Austrians and Prussians entered Holstein, marched across that Duchy, and in the early part of February began the invasion of Schleswig. The relations of the Allied troops to the Federal army of occupation were very remarkable. Both were opposed to the Danes, but they were equally opposed to one another; had they dared to do so, the Saxons would have opposed the Prussian advance. As it was they sullenly watched the Prussian and Austrian columns marching north to the invasion of Denmark. It was the first time that the remodelled Prussian army had been tested on the field of battle; Bismarck had brought it about that they were fighting for the cause of Germany and in alliance with Austria. As soon as war began, his own position improved. The King and the army were, of course, all the more confident in a Minister who had given them so good a cause of war and allowed them to take the field side by side with their old ally. Their superiority in number and discipline ensured success in the military operations; the Danes evacuated their first position at the Dannewirk; the German troops occupied the whole of Schleswig, then after some further delay advanced into Jutland, and finally began the siege of the strong fortification of the Düppel. The taking of this was a difficult piece of work, which, after some delay, was successfully carried out at the beginning of April. Meanwhile the diplomatic difficulties had continued. There had now come from England the proposal of a Conference. This Bismarck, always wishing to preserve the appearance of moderation, accepted. Before doing so, he knew that he had gained a very important ally. Napoleon was displeased with the English Government; he it was who suggested to Bismarck that the best solution of the difficulty would be the annexation of the Duchies to Prussia. It was just what Bismarck himself desired. Would he be able to bring it about? This was what was in his mind when he had to consider the attitude he should adopt at the Conference. He could not, of course, propose it openly; he might be able to arrange affairs so that in the universal confusion this solution should be welcomed. He first of all began to change his attitude towards the German agitation for Augustenburg; hitherto he had opposed and discouraged it; now he let it have free course. He wrote: "The present situation is such that it seems to me desirable to let loose the whole pack against the Danes at the Congress; the joint noise will work in the direction of making the subjugation of the Duchies to Denmark appear impossible to foreigners; they will have to consider programmes which the Prussian Government cannot lay before them."