The Unification of Germany into a German Empire with tight political and administrative integration, replacing the decentralized German Confederation and Holy Roman Empire, was officially proclaimed on 18 January 1871, in the Hall of Mirrors at the Palace of Versailles in France. Princes of the German states, excluding Austria-Hungary and its House of Habsburg-Lorraine (the dynasty that formerly ruled over the German princes during the German Confederation and Holy Roman Empire), gathered there to proclaim William I of Prussia and the House of Hohenzollern as German Emperor, following the French capitulation in the Franco-Prussian War.