The German Empire (Deutsches Reich) was a semi-constitutional monarchy: beginning with the unification of Germany and proclamation of William I of Prussia as German Emperor (January 18, 1871), effectively ending with the proclamation of the German "Weimar" Republic in 1918.
William II set Germany to begin colonial efforts in Africa and the Pacific. Germany took over various territories, which formed German Southwest Africa, German Kamerun, Togoland, and German East Africa. Germany gained some islands in the Pacific and the Chinese port of Qingdao. After World War I, Germany lost all of its overseas colonies.