Key takeaways
- Wikipedia dates the process from the North German Confederation Treaty of 18 August 1866 to the proclamation of the German Empire on 18 January 1871.
- Unification followed the 'Lesser Germany' model, leaving out Habsburg Austria, settled by the Peace of Prague after the 1866 war.
- Three wars drove it: against Denmark in 1864, Austria in 1866 and France in 1870–71.
- The US Office of the Historian notes the North German Confederation comprised 21 states plus Prussia, and was made obsolete by the 1871 Empire.
- Historians debate whether Bismarck had a master plan; Wikipedia notes post-1945 historians see more short-term opportunism.
The unification of Germany produced a single German nation-state under Prussian leadership, proclaimed on 18 January 1871, and it deliberately left Austria out. Wikipedia dates the process from the North German Confederation Treaty of 18 August 1866 to that proclamation in the Hall of Mirrors at Versailles — about four and a half years, built on three short wars and a great deal of diplomacy by Otto von Bismarck.
Here is how it happened, in order, and where historians still argue.
Hundreds of states and one question: with Austria or without?
The Office of the Historian describes eighteenth-century Germany as a conglomeration of more than 300 independent kingdoms, duchies, principalities and free cities. After the Holy Roman Empire was dissolved in 1806, the Congress of Vienna created a German Confederation under Habsburg leadership. Wikipedia describes the problem this left as "German dualism": both Austria and Prussia wanted to lead any united Germany. That gave two possible answers — a Großdeutschland, Greater Germany including Austria, or a Kleindeutschland, a Lesser Germany without it.
Economics tilted the field before politics did. Wikipedia credits the Zollverein, a customs union begun by Prussia in 1818 and joined by other states over the following decades, with reducing barriers between the German states and creating a sense of economic unity, especially for the industrial Rhineland, Saar and Ruhr.
1848: a crown refused
The liberal route came first and failed. On 27 March 1849, Wikipedia records, the Frankfurt Parliament passed a constitution and the next month offered the title of emperor to Frederick William IV of Prussia. He refused — publicly because the princes had not consented, privately, Wikipedia says, because he feared Austria or Russia and would not accept a crown of "clay" from an elected assembly. The Frankfurt liberals did, however, settle on the kleindeutsch solution that 1871 would eventually deliver.
Bismarck, the army and "iron and blood"
A budget crisis over army reform brought Bismarck to power as Minister-President of Prussia in 1862. On 30 September 1862 he told the budget committee that the great questions of the time would be decided "not by speeches and majority decisions — that was the great mistake of 1848 and 1849 — but by iron and blood." Wikipedia cautions that the line is often misread as bloodlust; it also referred to the German states' ability to produce iron and related war materials, and the willingness to use them if necessary.
Behind him stood the reorganised army of Albrecht von Roon and the general staff of Helmuth von Moltke. Wikipedia describes the needle gun, one of the first bolt-action rifles used in war, as aiding the Prussians in the next two wars: in the time a muzzle-loader fired once and had to be reloaded standing up, the needle rifle could be loaded and fired five times while the soldier lay prone. Five shots to one is a fivefold rate of fire.
The three wars, 1864–1871
| War | Opponent | Outcome for unification |
|---|---|---|
| Second Schleswig War, 1864 | Denmark | Prussia and Austria take Schleswig and Holstein (Peace of Vienna, 30 October 1864) |
| Austro-Prussian War, 1866 | Austria and allies | Victory at Königgrätz; Peace of Prague ends the German Confederation and excludes Austria |
| Franco-Prussian War, 1870–71 | France | Southern states fight alongside Prussia and join the new Empire |
The 1866 war was fought with newly unified Italy as Prussia's ally — the same war that brought Venetia to Italy, described in the unification of Italy. Its result was the North German Confederation, whose constitution, based largely on Bismarck's draft, was adopted on 1 July 1867. The Office of the Historian describes it as a federal state of 21 German states plus Prussia, with Württemberg, Baden, Bavaria, Austria and Southern Hesse outside it. The southern states signed alliance treaties with Prussia instead.
The final war came out of Spain. When the Spanish throne was offered to Leopold of Hohenzollern-Sigmaringen in 1870, France objected; Leopold withdrew, but the French ambassador pressed Wilhelm I at Ems for a promise that no Hohenzollern would ever stand. Wilhelm refused and telegraphed an account to Bismarck, who, Wikipedia records, shortened and sharpened it into a press statement — the Ems Dispatch — that provoked fury in France. France declared war, and the southern German states joined Prussia under their 1866 alliances. Napoleon III and an entire army were captured at Sedan on 1 September 1870.
1871: one empire, four dates
The proclamation of Wilhelm as German Emperor at Versailles on 18 January 1871 is the date usually celebrated. Wikipedia lists three other legally meaningful ones: 1 January 1871, when the southern states acceded and the name "German Empire" was adopted; 4 May, when the permanent constitution came into force; and 10 May, the Treaty of Frankfurt, in which France recognised the Empire and ceded Alsace and part of Lorraine. From 1 January to 10 May 1871 is 129 days — a reminder, set out in how historians date events, that "when" depends on what you count. The Office of the Historian notes the United States moved to recognise the new Empire in 1871.
Did Bismarck plan it all?
Wikipedia states that historians debate whether Bismarck had a master plan to unify Germany or simply set out to expand Prussian power. The traditional view, advanced largely by pro-Prussian historians of the late nineteenth and early twentieth centuries, saw unification as his goal throughout; post-1945 historians see more short-term opportunism in how he manipulated events in 1866 and 1870. Wikipedia also concludes that factors beyond Bismarck's Realpolitik — economics, nationalism, the memory of the wars against Napoleon (see Napoleon's rise and fall) — drove the process.
The new Empire's place in the European system of the next forty years is part of what started the First World War.
World History Timeline Sim, our app, organises events by country and year, which helps when one process spans 1864 to 1871. Its Time Travel Mode plays out alternative outcomes that are simulations, not what happened, and the app works as a companion to coursework rather than a replacement for it. More guides are under education and brain training.
Good to know
Frequently asked questions
Why is 18 January 1871 not the only founding date of the German Empire?
What did Bismarck mean by blood and iron?
Which German states stayed out of the North German Confederation?
What was the Ems Dispatch?
Sources
- A Guide to the United States' History of Recognition, Diplomatic, and Consular Relations, by Country, since 1776: North German Confederation (opens in a new tab)Office of the Historian, US Department of State — accessed
- A Guide to the United States' History of Recognition, Diplomatic, and Consular Relations, by Country, since 1776: Germany (opens in a new tab)Office of the Historian, US Department of State — accessed
- Unification of Germany (opens in a new tab)Wikipedia — accessed
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