Schleswig-Holstein Question

The Schleswig-Holstein Question (German: Schleswig-Holsteinische Frage; Danish: Spørgsmålet om Sønderjylland og Holsten) was a complex set of diplomatic and other issues arising in the 19th century from the relations of two duchies, Schleswig (Danish: Sønderjylland/Slesvig) and Holstein (Danish: Holsten), to the Danish crown and to the German Confederation. The British statesman Lord Palmerston is reported to have said: “Only three people have ever really understood the Schleswig-Holstein business—the Prince Consort, who is dead—a German professor, who has gone mad—and I, who have forgotten all about it."

Schleswig was a part of Denmark during the Viking Age, and became a Danish duchy in the 12th century. Denmark repeatedly tried to reintegrate the Duchy of Schleswig into the Danish kingdom. On March 27, 1848, Frederick VII of Denmark announced to the people of Schleswig the promulgation of a liberal constitution under which the duchy, while preserving its local autonomy, would become an integral part of Denmark. This led to an open uprising by Schleswig-Holstein's large German majority in support of independence from Denmark and of close association with the German Confederation. The military intervention of the Kingdom of Prussia supported the uprising: the Prussian army drove Denmark's troops from Schleswig and Holstein in the First Schleswig War of 1848–1851. The second attempt to reintegrate the Duchy of Schleswig into the Danish kingdom, initiated by the signing by King Christian IX of Denmark of the November Constitution in 1863, was seen as a violation of the and led to the Second Schleswig War of 1864.

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