This step was the more remarkable because Napoleon had received the news of the Treaty of Gastein with marked displeasure, and had given public expression to his opinions.

Bismarck saw Drouyn de Lhuys at Paris and then went on to Biarritz where the Emperor was; for ten days he lived there in constant association with the Imperial family.

The personal impression which he made was very favourable: "A really great man," wrote Merimee, "free from feeling and full of _esprit_." He saw Napoleon again on his return through Paris; the two succeeded in coming to an understanding.

Napoleon assured him that he might depend on the absolute neutrality of France, in case of a war between Prussia and Austria; it was agreed also that the annexation of the Duchies to Prussia would not be an increase of territory which would cause any uneasiness at Paris; Napoleon would view it with favour.
Bismarck went farther than this; he opened the subject of a complete reform of the German Constitution on the lines that Prussia was to have a free hand in the north of Germany; he pointed out "that the acquisition of the Duchies would only be an earnest for the fulfilment of the pledge which history had laid upon the State of Prussia; for the future prosecution of it we need the most friendly relations with France.

It seems to me in the interest of France to encourage Prussia in the ambitious fulfilment of her national duty." The Emperor acquiesced; as we know, the division of Europe into large national States was what he meant by Napoleonic ideas; he was willing enough to help in Germany a change such as that he had brought about in Italy.