The German Empire (German: Deutsches Kaiserreich), officially the German Reich, was the historical German nation state that existed from the unification of Germany in 1871 to the abdication of Kaiser Wilhelm II in November 1918, when Germany became a federal republic.
The German Empire consisted of 27 constituent territories, with most being ruled by royal families. This included four kingdoms, six grand duchies, six duchies (five after 1876), seven principalities, three free Hanseatic cities, and one imperial territory. Although the Kingdom of Prussia contained most of the Empire's population and territory, it played a lesser role.
After 1850, the states of Germany had rapidly become industrialized, with particular strengths in coal, iron (and later steel), chemicals, and railways. In 1871 it had a population of 41 million people, and by 1913 this had increased to 68 million. A heavily rural collection of states in 1815, the united Germany became predominantly urban. During its 47 years of existence, the German Empire operated as an industrial, technological, and scientific giant, gaining more Nobel Prizes in science than any other country.
The German colonial empire (German: Deutsches Kolonialreich) constituted the overseas colonies, dependencies and territories of Imperial Germany. Short-lived attempts of colonization by individual German states had occurred in preceding centuries, but crucial colonial efforts only began in 1884 with the Scramble for Africa. Germany lost control when World War I began in 1914 and its colonies were seized by its enemies in the first weeks of the war. However some military units held out for a while longer: German South-West Africa surrendered in 1915, Kamerun in 1916 and German East Africa only in 1918 by end of the war. Germany's colonial empire was officially confiscated with the Treaty of Versailles after her defeat in the war and the various units became League of Nations mandates under the supervision (but not ownership) of one of the victorious powers.
Until their 1871 unification, the German states had not concentrated on the development of a navy, and this essentially had precluded German participation in earlier imperialist scrambles for remote colonial territory – the so-called "place in the sun". Germany seemed destined to play catch-up. The German states prior to 1870 had retained separate political structures and goals, and German foreign policy up to and including the age of Otto von Bismarck concentrated on resolving the "German question" in Europe and securing German interests on the continent.
Otto von Bismarck (1 April 1815 – 30 July 1898) was a conservative Prussian statesman who dominated German and European affairs from the 1860s until 1890. In the 1860s he engineered a series of wars that unified the German states, significantly and deliberately excluding Austria, into a powerful German Empire under Prussian leadership. With that accomplished by 1871 he skillfully used balance of power diplomacy to preserve German hegemony in a Europe which, despite many disputes and war scares, remained at peace. For historian Eric Hobsbawm, it was Bismarck who "remained undisputed world champion at the game of multilateral diplomatic chess for almost twenty years after 1871, [and] devoted himself exclusively, and successfully, to maintaining peace between the powers."