However, following the Austro-Prussian War, in which Prussia invaded and occupied the duchies, they became Prussian, but the title Duke of Schleswig-Holstein was still claimed by Prince Christian's family.
Cu toate acestea, ca urmare a războiului austro-prusac, în care Prusia a invadat și ocupat ducatele, ele au devenit prusace iar titlul "Duce de Schleswig-Holstein" a fost revendicat de familia Prințului Christian.