Seven Weeks' War

Austro-Prussian War (Seven Weeks' War)
Part of the wars of German unification
Battle of Königgrätz, by Georg Bleibtreu. Oil on canvas, 1869.
Date 14 June – 23 August 1866 (2 months and 9 days) Location Bohemia, Germany, Italy and Adriatic Sea Result Prussian-led coalition victory Territorial changes Prussia annexes parts of Bavaria, Hanover, Hesse-Kassel, parts of Hesse-Darmstadt, Holstein, Schleswig, Nassau, and Frankfurt Italy annexes Venetia and part of Friuli Dissolution of the German Confederation Formation of the North German Confederation Exclusion of Austria from Germany Formation of Austria-Hungary
Belligerents
Austria-led German Confederation states  Austria  Bavaria  Saxony (to 15-16 June)  Hanover (to 15-16 June)  Württemberg Hesse-Kassel (to 15-16 June)  Baden Hesse-Darmstadt	Prussia-led German Confederation states Prussia Mecklenburg-Schwerin Oldenburg Italy (from 20 June)
Commanders and leaders
Franz Joseph I Albrecht von Teschen Ludwig von Benedek	Wilhelm I Otto von Bismarck Helmuth von Moltke
Strength
600,000	500,000
Casualties and losses
Austria: over 71,000 killed, wounded and missing	37,000 dead or wounded (German and Italian)

Austria-led German Confederation states

Prussia-led German Confederation states

Italy (from 20 June)

The Austro-Prussian War or Seven Weeks' War (also known as the Unification War,Prussian–German War, German Civil War, War of 1866, Brothers War, or Fraternal War, and in Germany as the German War) was a war fought in 1866 between the German Confederation under the leadership of the Austrian Empire and its German allies on one side and the Kingdom of Prussia with its German allies on the other, that resulted in Prussian dominance over the German states. This conflict also paralleled the Third Independence War of Italian unification.

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Wikipedia