In Austria, Prussia and Austria's victorious war against Denmark comes to an official end with the Treaty of Vienna
The war, fought largely over the fate of the German-Danish provinces of Holstein and Schleswig, had begun in February 1864. The Danes had held their own at sea but were defeated heavily by Prussian and Austrian land forces. The Treaty of Vienna ceded both provinces and other areas to Prussia and Austria, reducing both Denmark's land area and population by around 40%. (By John Osborne)
Michael Embree, Bismarck's First War: The Campaign of Schleswig and Jutland 1864 (Solihull, England: Helion and Company, Ltd, 2007), 343-344.