German unification was formally achieved on 18 January 1871 when Wilhelm became Emperor of Germany in the Hall of Mirrors at Versailles after Prussia's victory in the Franco-Prussian War. However, the transition of German-speaking populations into a federated organization had occurred unofficially over nearly a century through experimentation. While unification united many states, it also exposed religious, linguistic, social and cultural differences between inhabitants, showing that 1871 was just one moment in the larger process of unification.