What sovereign duke of the Duchy of Saxe-Coburg and Gotha, composed the opera Diana von Solange in 1858?
Ernest II, Duke of Saxe-Coburg and Gotha Ernest II (German: "Ernst August Karl Johann Leopold Alexander Eduard"; 21 June 1818 – 22 August 1893) was the sovereign duke of the Duchy of Saxe-Coburg and Gotha, reigning from 1844 to his death. Ernest was born in Coburg as the eldest child of Ernest I, Duke of Saxe-Coburg-Saalfeld, and his duchess, Princess Louise of Saxe-Gotha-Altenburg. Fourteen months later, his younger brother Prince Albert was born, who became consort of Queen Victoria of the United Kingdom. Ernest's father became Duke of Saxe-Coburg and Gotha in 1826 through an exchange of territories.
Duc de Dalberg The title of Duc de Dalberg was created by the French Emperor Napoleon I on 14 April 1810 for Emmerich von Dalberg, the nephew of Karl Theodor von Dalberg, Prince-Primate of the Confederation of the Rhine and Grand Duke of Frankfurt. He died on 27 April 1833. His daughter and heiress married firstly Sir Richard Acton, 7th Baronet (by whom she was the mother of John Dalberg-Acton, 1st Baron Acton) and secondly Granville George Leveson-Gower, 2nd Earl Granville, but as the Duke had no sons, the title became extinct.