|Grand Duke of Saxe-Weimar-Eisenach|
|Reign||5 January 1901 – 9 November 1918|
|Successor||Grand Duchy abolished|
10 June 1876|
|Died||24 April 1923
Henryków, Lower Silesian Voivodeship, German: Heinrichau, Silesia
|Spouse||Princess Caroline Reuss of Greiz
Princess Feodora of Saxe-Meiningen
|Issue||Sophie, Princess of Schwarzburg
Charles Augustus, Hereditary Grand Duke of Saxe-Weimar-Eisenach
|House||House of Saxe-Weimar-Eisenach|
|Father||Charles Augustus, Hereditary Grand Duke of Saxe-Weimar-Eisenach|
|Mother||Princess Pauline of Saxe-Weimar-Eisenach|
Wilhelm Ernst Karl Alexander Friedrich Heinrich Bernhard Albert Georg Hermann (English: William Ernest Charles Alexander Frederick Henry Bernard Albert George Herman) (10 June 1876 – 24 April 1923) was the last Grand Duke of Saxe-Weimar-Eisenach.
He succeeded his grandfather Karl Alexander as Grand Duke on 5 January 1901, as his father had predeceased him.
His heir was a distant cousin, Prince Hermann of Saxe-Weimar-Eisenach, until his disinheritance in 1909. Hermann's younger brother subsequently served as heir presumptive to the duchy of Saxe-Weimar-Eisenach until the birth of William Ernest's eldest son.
Wilhelm Ernst created the new Weimar city center under the direction of Hans Olde, Henry van de Velde, and Adolf Brütt. Also, he also had the University of Jena rebuilt by Theodor Fischer, and also reconstructed Weimar's famous theatres. The improvements to the city included a marble statue of his predecessor Charles Alexander, which was completed in 1911. It was placed in a setting designed by Brütt. The placement of the setting was designed to distinguish the "Old Town" from the newly built area. A preservation law for the "Old Town" barred it to the "art nouveau" style which was used in the new area.
According to the Dutch constitution, Wilhelm Ernst was in the line for the throne of the Netherlands (as the grandson of Princess Sophie of the Netherlands) after Queen Wilhelmina. At the beginning of the 20th century, the Dutch feared the possibility of German influence or even annexation of the Netherlands. In order to prevent this, some lawyers tried to change the constitution to exclude Wilhelm Ernst from the succession. Another proposal, however, was this: if Wilhelmina would die childless, then he or his offspring would have to choose between the Dutch and the Weimar throne. The birth of Wilhelmina's daughter Juliana in 1909 lessened the chance for any member of the house of Wettin (Saxe-Weimar-Eisenach branch) to inherit the Dutch throne. With the amendment to the constitution of 1922, which restricted the right of succession to the offspring of Wilhelmina, the possibility disappeared entirely.
On 9 November 1918 Wilhelm Ernst - along with the rest of the German monarchs following the defeat of Germany in World War I - was forced to abdicate. His throne and all his lands were relinquished and he fled with his family to the family estate in Silesia, where he died five years later.
Despite all his work for Weimar during his government, Wilhelm Ernst was a hated ruler. This was for his private life, where he was known to be a sadist; the day of his abdication, he was called the "most unpopular prince in all Germany".
He died in Heinrichau in Silesia.
In Bückeburg on 30 April 1903 Wilhelm Ernst married firstly with Princess Caroline Reuss of Greiz, a daughter of Prince Heinrich XXII Reuss of Greiz. This marriage was childless and ended in 1905 with the death of Caroline under mysterious circumstances. The official cause of death was pneumonia following influenza; other sources have suggested suicide.
They had four children:
|Princess Sophie Luise Adelheid Marie Olga Carola||20 March 1911||21 November 1988||married Friedrich Günther, Prince of Schwarzburg; the marriage ended in divorce less than a year later. There were no children.|
|Karl August Wilhelm Ernst Friedrich Georg Johann Albrecht, Hereditary Grand Duke of Saxe-Weimar-Eisenach||28 July 1912||14 October 1988||married Baroness Elisabeth of Wangenheim-Winterstein; had issue|
|Prince Bernhard Friedrich Viktor||3 March 1917||23 March 1986||His daughter Katharina Feodora Adelheid Sabine Sophie Felicitas Sieglinde, Princess of Saxe-Weimar-Eisenach (born 30 November 1943) married Prince Emanuel Joseph von Hohenzollern-Emden, son of Franz Joseph, Prince of Hohenzollern-Emden, on 25 May 1968 (divorced in 1985)|
|Prince Georg Wilhelm Albert Bernhard||24 November 1921||11 March 2011||changed name for Jörg Brena in 1953 and renounced his succession rights|
|Ancestors of William Ernest, Grand Duke of Saxe-Weimar-Eisenach|
|Grand Duke of Saxe-Weimar-Eisenach
5 January 1901 – 9 November 1918
|Grand Duchy abolished|
|Titles in pretence|
|Grand Duchy abolished||Grand Duke of Saxe-Weimar-Eisenach
5 January 1901 – 24 April 1923