Piano sonatas (Beethoven)
Ludwig van Beethoven wrote his 32 piano sonatas between 1795 and 1822. Although originally not intended to be a meaningful whole, as a set they compose one of the most important collections of works in the history of music. Hans von Bülow called them "The New Testament" of the piano literature (Johann Sebastian Bach's "The Well-Tempered Clavier" being "The Old Testament").
Jean-Pierre Duport
Duport and his younger brother were acquainted with Beethoven: in February 1796 Beethoven had left Vienna for a five-month concert tour which took him to Prague (accompanied by Prince Lichnowsky, who had travelled there with Mozart in 1789), Dresden, Leipzig, and Berlin, where he was inspired by the high level and quality of musical activity at the court of King Friedrich Wilhelm II of Prussia, at which Jean-Pierre was director of chamber music. On the Potsdam court, Beethoven's two opus 5 cello sonatas were composed for him. Either Duport or his younger brother played the cello part with Beethoven at the keyboard at the premier performance of these sonatas.