The Kingdom of Prussia was one of the dominant powers in Central Europe. It was under the leadership of King Wilhelm I, who was (together with Otto von Bismarck) eager to create a central unified Germany. In the past, the kingdom has undergone significant modernisation in the military, economy and administration, which gave it a competitive advantage over rivals. Their army was one of the most powerful in Europe, and the economy was booming, fueled by industrialisation, the expansion of railways and other modes of transportation.
In 1866, Prussia annexed the Kingdom of Hanover as a direct result of the Austro-Prussian War, which aimed to weaken Austria’s influence and establish Prussia as the leading German state in the Confederation. Hanover had sided with Austria during the war, and after the Austrians lost at the Battle of Königgrätz, they lost their independent status.