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.
Maria Theresa Maria Theresa Walburga Amalia Christina (German: "Maria Theresia" ] ; 13 May 1717 – 29 November 1780) was the only female ruler of the Habsburg dominions and the last of the House of Habsburg. She was the sovereign of Austria, Hungary, Croatia, Bohemia, Transylvania, Mantua, Milan, Lodomeria and Galicia, the Austrian Netherlands and Parma. By marriage, she was Duchess of Lorraine, Grand Duchess of Tuscany and Holy Roman Empress.