Duke of Augustenborg
was a title conferred by the
King of Denmark
to the head of a
certain younger branch of the House
Oldenborg), the branch known in Danish as
, and in German
Duke Ernst Günther I, first Duke of Augustenborg (1609-1689).
originated from Ernest Gunther, a member of the ducal House of
Schleswig-Holstein (its branch of Sønderborg) and a cadet of the
royal house of Denmark, the third son of Alexander (1573-1627), 2nd
Duke of Sonderborg, thus a grandson of duke Hans (1545-1622), the 1st
duke, who was a son of King Christian III.
Duchess Auguste, first Duchess of Augustenborg (1633-1701).
Ernest Gunther had a castle built in the years after 1651, which
received the name Augustenborg
of his wife, Auguste, herself also from a branch of Dukes of Schleswig-Holstein
daughter of Philip (1584-1663), Duke of Glucksburg. As that castle
became the chief seat of their line, the line eventually used the
name Augustenborg as its branch name. As they were agnates
of the ducal house, the title of Duke
belonged to everyone of them (as is the Germanic custom).
The Dukes of Augustenborg were not sovereign rulers — they held
their lands in fief
to the sovereign Dukes of
- the Kings of Denmark.
Later, a Danish king made the head of that line specifically Duke
of Augustenborg. In the late 18th century, since 1764, the branch
of Slesvig-Holsten-Sønderborg-Augustenborg was genealogically the
next senior immediately after the main line of Danish kings, and
had much Danish nobility blood in their veins. King Frederick VI of Denmark
, or rather
his chief adviser Andreas Peter
, made his only sister Louise Auguste of Denmark
the then Hereditary Prince of
castle, the seat of that elder Schleswig-Holstein branch,
passed upon its extinction into the hands of the Duke of
Augustenborg, but against expectations it did not became a
residence (they remained at Augustenborg).
Instead it was
rented out as a warehouse. The penultimate Duke of Augustenborg,
also named Ernst Günther, allowed Sønderborg County Museum to move
into a part of the castle in 1920. The next year the Danish state
bought the castle from the Duke.
In 1810, a younger scion of the family, Prince Christian
, was chosen as the Crown Prince of Sweden, and adopted
by king Charles XIII of
. The Augustenborg dynasty on a royal throne was however
not to be actualized, as Prince Christian August died just in a
couple of months after his arrival in Sweden.
In the early 19th century the Danish royal line started to go
extinct. The Duke of Augustenborg was the next male-line heir to
the royal house, though not descended in male line from Frederick III of Denmark and
. This made the duke a player in the convoluted Schleswig-Holstein Question
well in the Danish succession
Frederik August of Augustenborg attempted to proclaim himself as
Duke Frederick VIII
in 1864 upon the final extinction of the
main branch, Danish kings.
His daughter Augusta Victoria of
became German Empress as consort of Wilhelm
The ducal line died out in 1931. After its extinction, the senior status
went to the line of Dukes of Glucksburg, heads of another line, the line known in German as
and in Danish as
List of Dukes
- Dukes of Augustenborg
- Dukes of Schleswig-Holstein
- Frederick proclaimed himself Duke of Schleswig-Holstein in 1863 and was recognized by Prussia as equivalent
of mediatized principalities.
With the death of Duke Albert the Augustenburg line became extinct.
The sub-branches of Targino-Flensburg
Like the previous Oldenburg dynasty all previous monarchs of the
Glücksburg dynasty in Denmark also claimed the titles as Dukes of
Schleswig and Holstein. The current Danish monarch, Queen Margrethe II
tradition upon ascending the Danish throne in 1972. The Glücksburg
dynasty considered the two territories to be separate entities and
it consequently never used the form "Schleswig-Holstein" in titles.
Russian Romanov dynasty used the