Ludwig van Beethoven’s only opera, Fidelio, has the opus number 72. The opera began as Leonore, oder Der Triumph der ehelichen Liebe and went through substantial revisions before reaching the version generally known as Fidelio.
Beethoven’s opera tells of Leonore, who disguises herself as a man named Fidelio to rescue her husband Florestan from political imprisonment. The story combines personal loyalty with ideals of justice and freedom, themes that appealed strongly to Beethoven and his era.
The first version premiered in Vienna in 1805, but Beethoven revised the opera for later productions. The final version was first performed in 1814, when the work acquired the title Fidelio. Its four overtures are also frequently discussed: the so-called Leonore Overtures are not simply interchangeable introductions to the final opera.
The opus number Op. 72 identifies the opera in Beethoven’s catalogue. Earlier versions and related overtures have their own historical labels, which is why references to “Beethoven’s opera” can involve several different premiere dates.