"Prussia had for long been an expansionist power. Despite losses during the Napoleonic Wars, in 1815 she had been awarded a part of Saxony and territory in western Germany with the object of raising a bulwark against France and of buttressing Holland. Thereafter it was her policy to weld together her eastern and western territories. From 1828 she formed a series of unions (Zollvereine). In 1834 the German Zollverein was created and expanded under the impact of the development of German railways and industrialisation. By the 1850s (der Gründerjahre) Prussia had gained an economic [domination] over Austria, but it was not until Bismark came to power [1862] that she challenged Austria's political leadership -- over the question of Schleswig and Holstein. In 1864 Austria and Prussia, acting on behalf of the German Confederation, went to war with Denmark, defeated her, and took over the administration of these two duchies (Convention of Gastein, 1865). " HarperCollins Atlas of World History; pp.216-217