What is the title of the only opera completed by Jean Sibelius?

Jean Sibelius’s only completed opera is The Maiden in the Tower.

Sibelius composed The Maiden in the Tower, or Jungfrun i tornet, in 1896. It is a one-act opera in Swedish, with a libretto by Rafael Herlin. The story centers on a maiden held in a tower by a bailiff and rescued with the help of a castellan and his mother.

The opera received its first performance in Helsinki on 7 November 1896 as part of a benefit concert. Sibelius later withdrew the work, and it was not published during his lifetime. Its limited performance history has made it less familiar than his symphonies and tone poems.

Sibelius wrote other vocal and dramatic music, including music connected with the Finnish national epic Kalevala. Kullervo is a major symphonic poem or symphonic work with voices, not an opera, while The Maiden in the Tower is the completed opera in his catalog.