North Schleswig Germans

Approximately 15,000 persons in Denmark belong to an ethnic German minority traditionally referred to as hjemmetyskere meaning "domestic Germans" in Danish, and as Nordschleswiger in German. This minority of Germans hold Danish citizenship and self-identify as ethnic Germans. They continue to use German and South Jutlandic as their home languages. Furthermore, there are also several thousand German citizens residing in Denmark with no historical connection to this group.

In 1920, in the aftermath of World War I, two Schleswig Plebiscites were held in the northernmost part of the Prussian Province of Schleswig-Holstein (the northern half of the former Duchy of Schleswig). The plebiscites were held in two zones that were defined by Denmark according to the ideas of the Danish historian Hans Victor Clausen. The northern Zone I was deliminated according to Clausen's estimation of where the local rural population identified itself as Danish, a survey published in 1891. Clausen travelled extensively on both sides of the eventual border, in an attempt determine which communities that would vote for a return to Danish rule, and concluded that this was the case north of the Skelbækken creek, where most rural communities were both Danish-speaking and pro-Danish, while the communities south of this line were overwhelmingly pro-German (though some of these communities were also primarily Danish-speaking). Near Tønder, he deviated from this system, and included the German-majority towns of Tønder and Højer into the northern sector for economic purposes, and to achieve a line following a dyke, consequently this line followed the dyke south of Højer.

The northern Zone I voted en bloc, i.e. as a unit with the majority deciding, and the result was 75% for Denmark and 25% for Germany, consequently resulting in a German minority north on the new border. In the southern Zone II, each parish/town voted for its own future allegiance, and all districts in Zone II showed German majorities. The eventual border was deliminated virtually identical with the border between Zones I and II.

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