Beethoven's Piano Sonata No. 23 in F minor, Op. 57 (colloquially known as the Appassionata) is among the three famous piano sonatas of his middle period (the others being the Waldstein, Op. 53 and Les Adieux, Op. 81a).  Composed during 1804 and 1805, and perhaps 1806, it was dedicated to Count Franz von Brunswick and the present first edition was published in February 1807 in Vienna. Unlike the early Sonata No. 8, Pathétique, the Appassionata was not named during the composer's lifetime, but was so labelled in 1838 by the publisher of a four-hand arrangement of the work. The numbering on the title page "LIVme Sonata" (like that of the first edition of the op. 54 sonata as "LIme Sonate") has been puzzling the musical world for over two centuries, with no satisfactory explanation having been offered thus far.