Significance

German unification fundamentally reshaped the European balance of power. The new German Empire was the strongest military and industrial power on the European continent. Bismarck's success demonstrated that nationalism could be harnessed by conservative regimes for state-building, not just by liberals for revolution. The annexation of Alsace-Lorraine became a permanent French grievance that would help trigger the First World War. The new Germany's rapid industrialization and naval ambitions would unsettle European diplomacy for the next forty years.

Compare Italian and German unification: Both were achieved by the strongest regional state (Sardinia for Italy, Prussia for Germany) at the expense of older imperial powers (Austria) with help from a strong leader (Cavour, Bismarck). Both used military action combined with diplomatic maneuvering. Both produced constitutional monarchies. The differences: Italy retained significant regional disparities; Germany was more militarized and more dominant. Italy joined the European great powers as a relatively weak member; Germany joined them as a transformative new force.