We mark the opening on May 25, 1869 – 151 years ago today - of the Vienna Court Opera (or Wiener Hofoper), which has been known since 1921 as the Vienna State Opera (or Wiener Staatsoper). The opening was a gala event: a performance of Wolfgang Mozart’s opera Don Giovanni attended by, among many others, Emperor Franz Josef I and his bride, the Empress Elizabeth of Austria (know to her intimates as Sisi).