The next three years Bismarck devoted himself to diplomatic intrigues in order to cement the union of the German States,—­for the Luxemburg treaty was well known to be a mere truce,—­and Napoleon did the same to weaken the union.  In the meantime King William accepted an invitation of Napoleon to visit Paris at the time of the Great Exposition; and thither he went, accompanied by Counts Bismarck and Moltke.  The party was soon after joined by the Czar, accompanied by Prince Gortschakoff, who had the reputation of being the ablest diplomatist in Europe, next to Bismarck.  The meeting was a sort of carnival of peace, hollow and pretentious, with fetes and banquets and military displays innumerable.  The Prussian minister amused himself by feeling the national pulse, while Moltke took long walks to observe the fortifications of Paris.  When his royal guests had left, Napoleon travelled to Salzburg to meet the Austrian emperor, ostensibly to condole with him for the unfortunate fate of Maximilian in Mexico, but really to interchange political ideas.  Bismarck was not deceived, and openly maintained that the military and commercial interests of north and south Germany were identical.

In April, 1868, the Customs Parliament assembled in Berlin, as the first representative body of the entire nation that had as yet met.  Though convoked to discuss tobacco and cotton, the real object was to pave the way for “the consummation of the national destinies.”

Bismarck meanwhile conciliated Hanover, whose sovereign, King George, had been dethroned, by giving him a large personal indemnity, and by granting home rule to what was now a mere province of Prussia.  In Berlin, he resisted in the Reichstag the constitutional encroachments which the Liberal party aimed at,—­ever an autocrat rather than minister, having no faith in governmental responsibility to parliament.  Only one master he served, and that was the king, as Richelieu served Louis XIII.  Nor would he hear of a divided ministry; affairs were too complicated to permit him to be encumbered by colleagues.  He maintained that public affairs demanded quickness, energy, and unity of action; and it was certainly fortunate for Germany in the present crisis that the foreign policy was in the hands of a single man, and that man so able, decided, and astute as Bismarck.

All the while secret preparations for war went on in both Prussia and France.  French spies overran the Rhineland, and German draughtsmen were busy in the cities and plains of Alsace-Lorraine.  France had at last armed her soldiers with the breech-loading chassepot gun, by many thought to be superior to the needle-gun; and she had in addition secretly constructed a terrible and mysterious engine of war called mitrailleuse,—­a combination of gun-barrels fired by mechanism.  These were to effect great results.  On paper, four hundred and fifty thousand men were ready to rush as an irresistible avalanche on the Rhine provinces.