Premise: The Vienna State Opera (German: Wiener Staatsoper ) is an Austria opera house and opera company based in Vienna, Austria. It was originally called the Vienna Court Opera (Wiener Hofoper). In 1920, with the replacement of the Habsburg Monarchy by the First Austrian Republic, it was renamed the Vienna State Opera. The members of the Vienna Philharmonic are recruited from its orchestra.
Hypothesis: The opera house was referred to as the Vienna Court Opera for fifteen years before being changed to Vienna State Opera in 1920.