Joseph Kaspar Mertz, commonly known as Johann Kaspar Mertz, was born on 17 August 1806 in Pressburg (now Bratislava) and died on 14 October 1856 in Vienna. He was an Austro-Hungarian guitarist and composer who became active in Vienna’s guitar scene from around 1840, following in the tradition of figures such as Anton Diabelli and Mauro Giuliani. As a touring virtuoso he performed across Moravia, Poland, Russia, Berlin, and Dresden, and in 1842 married the concert pianist Josephine Plantin. In 1846 he nearly died from a strychnine overdose prescribed as a treatment for neuralgia, and spent the following year recovering with his wife’s care.

Mertz is regarded as one of the last major guitarist-composers of the Romantic era, whose lyrical, piano-influenced writing for guitar (partly credited to his wife’s influence) helped extend the instrument’s Romantic repertoire beyond the earlier Classical style of Giuliani and Sor.

Sources:

• https://en.wikipedia.org/wiki/Johann_Kaspar_Mertz