Bismarck pursued Realpolitik: practical policies designed to increase Prussian power rather than follow a fixed ideological principle. After Prussia defeated Austria in 1866, it organized the northern German states into the North German Confederation, while the southern states remained formally independent.
In 1870, the Hohenzollern candidature for the Spanish throne caused a diplomatic dispute with France. Bismarck edited and published the Ems Dispatch, making an exchange between King Wilhelm I and the French ambassador appear insulting. France declared war on Prussia on 19 July 1870, allowing Bismarck to present Prussia as the defender of Germany.
| Factor | Contribution to unification |
|---|---|
| Diplomacy | Bismarck encouraged France to declare war, preventing Prussia from appearing to be the aggressor. |
| German nationalism | The French threat encouraged the southern states to fight alongside Prussia. |
| Prussian military power | Forces commanded by Moltke defeated France rapidly and captured Napoleon III at Sedan. |
| Political settlement | German princes accepted a federal empire dominated by Prussia. |
On 18 January 1871, Wilhelm I was proclaimed German emperor at Versailles. The new German Empire included the southern states but excluded Austria, completing Bismarck's Kleindeutsch or "small German" solution under Prussian leadership.
A common misconception is that Bismarck unified Germany through the Franco-Prussian War alone. In an IB Paper 3 essay, explain causation by arguing that the war was the decisive final step, while military reform, Prussian economic influence, earlier diplomacy and nationalism made victory and political union possible.
