In the 16th century, the city became one of the first Scandinavian centres of Lutheranism during the Reformation. Prior to the Second Schleswig War of 1864, Haderslev was situated in the Duchy of Schleswig, a Danish fief, so its history is properly included in the contentious history of Schleswig-Holstein. From 1864 it was part of Prussia, and as such part of the North German Confederation, and from 1871 onwards, part of the German Empire. In the 1920 Schleswig Plebiscite that returned Northern Schleswig to Denmark, 38.6% of Haderslev's inhabitants voted for remaining part of Germany and 61.4% voted for the cession to Denmark. It was formerly the capital of the German Kreis Hadersleben and the Danish Haderslev County.
