There was a war over it in 1864, as the Prussians grew to become Germany taking the land from Denmark. https://en.wikipedia.org/wiki/Second_Schleswig_War https

There was a war over it in 1864, as the Prussians grew to become Germany taking the land from Denmark. https://en.wikipedia.org/wiki/Second_Schleswig_War https://en.wikipedia.org/wiki/Second_Schleswig_War