Austro-Prussian War
The pretext for the conflict was found in the dispute between Prussia and Austria over the administration of Schleswig-Holstein, which the two of them had conquered from Denmark and agreed to jointly occupy at the end of the Second Schleswig War in 1864. When Austria brought the dispute before the German Diet and also decided to convene the Diet of Holstein, Prussia declared that the Gastein Convention had thereby been nullified and invaded Holstein. When the German Diet responded by voting for a partial mobilization against Prussia, Bismarck claimed that the German Confederation was ended. Crown Prince Frederick "was the only member of the Prussian Crown Council to uphold the rights of the Duke of Augustenburg and oppose the idea of a war with Austria which he described as "fratricide"". Although he supported unification and the restoration of the medieval empire, "Fritz could not accept that war was the right way to unite Germany."
War of the Bavarian Succession
By the late 1770s, Joseph also faced important diplomatic obstacles in consolidating Habsburg influence in Central Europe. When the British had been Austria's allies, Austria could count on British support in its wars, but Britain was now allied with Prussia. In the Diplomatic Revolution, the French replaced the British as Austria's ally, but they were fickle, as Joseph discovered when Vergennes extricated Versailles from its obligations. Russia, which also had been an important Austrian ally for most of the Seven Years' War, sought opportunities for expansion at the expense of its weak neighbors. In 1778, that meant Poland and the Ottoman Empire, but Joseph fully understood the danger of appearing weak in Russia's eyes: Habsburg lands could be carved off easily by the cagey Catherine's diplomatic knife. Still, Frederick of Prussia was the most definite enemy, as he had been throughout the reigns of Theresa and Franz before him, when the Prussian state's emergence as a player on the European stage had occurred at Habsburg expense, first with the loss of Silesia, and later in the 1750s and 1760s. Joseph sought to unify the different portions of his realm, not the German states as a whole, and to establish Habsburg hegemony in German-speaking central Europe beginning with the partition of Bavaria.