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."
Franco-Austrian Alliance
The Alliance had its heyday during the Seven Years' War when France and Austria joined forces to fight the mutual enemy of Prussia. Following the allies' defeat in that war, the intimacy of the alliance weakened, and by the 1780s it had become something closer to a formality—when Austria briefly considered the idea of entering the American War of Independence on Britain's side against France. By the time of the French Revolution—when France first declared itself a constitutional monarchy, and then overthrew and executed its king—it had collapsed entirely and Austria actively tried to restore the French monarchy by going to war with the new French Republic.