Johann Kaspar Mertz (born August 17, 1806 in Pressburg (now Bratislava); died October 14, 1856 in Vienna) was an Austrian composer and guitarist of the Romantic period.
Caspar Joseph Mertz (baptized Casparus Josephus Mertz) was born in Pressburg, now Bratislava (Slovakia), then the capital of the Kingdom of Hungary and part of the Austrian Empire. He never used his full name in his performances and publications, but only the initials “J. K.”. The name “Johann Kaspar” first appeared in 1901 in the German guitar magazine “Der Guitarrefreund” and has been used incorrectly ever since. In 1900, J. M. Miller used the name “Joseph K. Mertz” for his publication of three previously unpublished manuscripts by Mertz in Three Compositions For Guitar.
He worked in Vienna (ca. 1840-1856), where various prominent guitarists lived, including Anton Diabelli, Mauro Giuliani, Wenceslaus Matiegka, and Simon Molitor. As a virtuoso, he earned a solid reputation as a performer. He toured Moravia, Poland, and Russia and performed in Berlin and Dresden. In 1846, Mertz nearly died from an overdose of strychnine, which had been prescribed to him for the treatment of neuralgia. Over the course of the following year, he was nursed back to health in the presence of his wife, the concert pianist Josephine Plantin, whom he had married in 1842. Some speculation suggests that listening to his wife’s romantic piano pieces during his recovery may have influenced the sound and unusual right-hand technique he used for the Bardenklänge, Op. 13 (1847).
Unlike most of his contemporaries, Mertz’s guitar music was based on the pianistic models of Liszt, Chopin, Mendelssohn, Schubert, and Schumann, rather than the classical models of Mozart and Haydn (like Sor and Aguado) or the bel canto style of Rossini (like Giuliani). However, his date of birth suggests that this was the logical influence, as Sor was born in 1778, Aguado in 1784, and Giuliani in 1781, while Mertz was born in 1806, a difference of about 25 years.
The Bardenklänge are probably Mertz’s most important contribution to the guitar repertoire (a series of character pieces modeled on Schumann), together with the great fantasies La rimembranza, Pensée fugitive, and Harmonie du soir, which are considered a trilogy, the most technically demanding pieces Mertz wrote and which are clearly inspired by Liszt’s piano music.