The Schleswig-Holstein War of 1864 was the first of three wars which are credited with bringing about the unification of Germany into a single state under the authority of the Prussian crown. The second war was the Austro-Prussian War of 1866 and the third and final war was the Franco-Prussian War of 1870. In January 1871, a ceremony was held in Versailles which made William I of Prussia the German Emperor of the now unified German Empire. This, then, is the background of the building of the German Empire against which the relationship of Gerson Bleichröder and Otto von Bismarck played itself out.