Frederick VIII, Duke of Schleswig-Holstein (d. 1880)
Duke Frederick VIII (Danish: Frederik Christian August af Slesvig-Holsten-Sønderborg-Augustenborg; German: Friedrich Christian August Herzog von Schleswig-Holstein-Sonderburg-Augustenburg; July 6, 1829 – January 14, 1880) was the German pretender to the throne of Schleswig-Holstein from 1863, although in reality Prussia took overlordship and real administrative power.