Schleswig-Holstein-Sonderburg-Glücksburg in the context of "Glücksburg Castle"

Glücksburg (German pronunciation: [ˈɡlʏksˌbʊʁk] ; Danish: Lyksborg) is a small town northeast of Flensburg in the district of Schleswig-Flensburg, in Schleswig-Holstein, Germany.

It is situated on the south side of the Flensborg Fjord, an inlet of the Baltic Sea, approx. 10 km northeast of Flensburg. The town was originally the home of the family Schleswig-Holstein-Sonderburg-Glücksburg (or simply Glücksburg), members of which have reigned in the past in Greece and several northern German states. Members of the family still reign in Denmark and Norway since 1863 and 1905 respectively, and have reigned in the United Kingdom and the 14 other Commonwealth realms since the accession of Charles III in 2022.

This is a list of monarchs of Denmark, that is, the kings and queens regnant of Denmark. This includes:

• The Kingdom of Denmark (up to 1397)
  • Personal union of Denmark and Norway (1380–1397)
• The Kalmar Union (1397–1536)
  • Union of Denmark, Norway and Sweden (1397–1523)
  • Union of Denmark and Norway (1523–1536/1537)
• The United Kingdoms of Denmark–Norway (1536/1537–1814)
• The Kingdom of Denmark (1814–present)
  • Iceland (since the union between Denmark and Norway in 1380; independent kingdom in a personal union with Denmark 1918–1944; a sovereign republic since 1944)
  • Greenland (since the union between Denmark and Norway in 1380; effective Danish–Norwegian control began in 1721; integrated into the Danish realm in 1953; internal home rule introduced 1979; self-rule assumed in 2009; Greenland has two out of 179 seats in the Danish parliament Folketinget)
  • Faroe Islands (since the union between Denmark and Norway in 1380; County of Denmark 1816–1948; internal home rule introduced 1948; The Faroe Islands have two out of 179 seats in the Danish parliament Folketinget)

The House of Oldenburg held the Danish Crown between 1448 and 1863, when it passed to the house of Schleswig-Holstein-Sonderburg-Glücksburg, a cadet branch of the same house, patrilineally descended from King Christian III of Denmark. The kingdom had been elective (although the eldest son or brother of the previous king was usually elected) until 1660 when it became hereditary and absolutist. Until 1864, Denmark was also united in a personal union with the duchies of Holstein and Saxe-Lauenburg (1815–1864), and in a political and personal union with the Duchy of Schleswig.