Province of Schleswig-Holstein

It was created from the Duchies of Schleswig and Holstein, which had been conquered by Prussia and the Austrian Empire from Denmark in the Second War of Schleswig in 1864. Following the Austro-Prussian War in 1866, which ended in Austrian defeat, Schleswig and Holstein were annexed by decree of the King of Prussia on January 12, 1867. The province was created in 1868, and it incorporated the Duchy of Lauenburg from 1876 onward.

Following the defeat of Imperial Germany in World War I, the Allied powers organised two plebiscites in Northern and Central Schleswig on 10 February and 14 March 1920, respectively. In Northern Schleswig, 75% voted for reunification with Denmark and 25% for staying with Germany. In Central Schleswig, the situation was reversed, with 80% voting for Germany and 20% for Denmark. No vote ever took place in the southern third of Schleswig, as it was considered a foregone conclusion that almost all the inhabitants would vote to remain in Germany.

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