Das geheime Königreich (The Secret Kingdom) is an opera in one act with words and music by Ernst Krenek, his Op.
A note to the press by the publisher Universal Editio (UE), probably from the end of 1927 and entitled Ein Einakter-Zyklus (A cycle of one-acters) announces that Ernst Krenek composed three one-act operas after the success of Jonny spielt auf, to be premiered together at the Festspiele Wiesbaden of 1928.
[4] Das geheime Königreich was recorded in 1999, conducted by Marek Janowski, with Michael Kraus as the King and Claudia Barainsky as the Queen.
He notes similarities to Shakespeare's The Tempest and Mozart's Die Zauberflöte, with a King who wants to resign after a revolution, and his Jester, and a Queen who falls in love with a revolutionary leader, and is turned into a tree.
The stage director, David Hermann, placed it at the end of the evening, making the King the person who started as the Dictator in the first opera.