Increased nationalism in Germany made it more powerful.
Germany was the strongest military power on the continent. Germany’s position geographically was between large military powers.
Otto von Bismarck had to be as sure as possible that no one would attack Germany, at least no coalition.
First, in 1879, Bismarck made a secret alliance with Austria-Hungary. In 1881, Bismarck signed a tri-treaty with Russia, Austria, and Germany: the Alliance of Three Emperors.
In 1882, Italy joined this alliance, making a triple alliance along with Austria and Russia.
Germanisation plan which eliminated all non-German languages, cultures and ethnic groups and promoted German cultures in the German Empire.
Prussian Settlement Commission (1886-1918) was one such policy of Prussia that aimed at promoting Germanisation and eliminating all non-German elements from German Empire.
Under Bismarck, Germany maintained a stable and reliable foreign policy, because Bismarck maintained an anti-imperialistic stand and maintained diplomacy. Germany managed to stay on good terms with just about everyone but France.
Industrialization progressed dynamically in Germany. German manufacturers began to capture domestic markets from British import.
The German textiles and metal industries surpassed those of Britain in organization and technical efficiency and usurped British manufacturers in the domestic market.
Germany became the dominant economic power on the continent and was the second largest exporting nation after the US.
By the turn of the century, the German metals and engineering industries would be producing heavily for the free trade market of Britain.
By the time of World War I (1914-1918), The German economy switched to supplying its military with the proper equipment needed to fight the war.
This included the production of rifles (Gewehr 98), pistols (P08 Luger), and heavy weaponry (Maxim machine gun, Minenwerfer mortar, and several other heavy and light artillery pieces).
Additionally, Imperial Germany was leading in the sectors of Physics and Chemistry so that one third of all Nobel Prizes went to German inventors and researchers.
The unification of Germany also changed the balance of power in Europe in terms of substance and nature. It was also a factor behind the outbreak of World War I.