States and territories disestablished in the 1770s

dynasty of Dano-German dukes

Holstein-Glückstadt or Schleswig-Holstein-Glückstadt is the historiographical name, as well as contemporary shorthand name, for the parts of the duchies of Schleswig and Holstein that were ruled by the Kings of Denmark in their function as dukes of Schleswig and Holstein, thus also known as Royal Schleswig-Holstein. Other parts of the duchies were ruled by the Dukes of Schleswig-Holstein-Gottorp. The territories of Holstein-Glückstadt are located in present-day Denmark and Germany. The main centre of administration was Segeberg and from 1648 Glückstadt (founded in 1617) on the River Elbe.