Dreikönigsbündnis
Throughout the 19th century, Prussia continued to grow in power. In 1848, German revolutionaries set up the temporary Frankfurt Parliament, but failed in their aim of forming a united German homeland. The Prussians proposed an Erfurt Union of the German states, but this effort was torpedoed by the Austrians through the Punctation of Olmütz (1850), recreating the German Confederation. In response, Prussia sought to use the Zollverein customs union to increase its power among the German states. Under the leadership of Otto von Bismarck, Prussia expanded its sphere of influence and together with its German allies defeated Denmark in the Second Schleswig War and soon after Austria in the Austro-Prussian War, subsequently establishing the North German Confederation. In 1871, the Prussian coalition decisively defeated the Second French Empire in the Franco-Prussian War, annexing the German speaking region of Alsace-Lorraine. After taking Paris, Prussia and their allies proclaimed the formation of a united German Empire.