Franz Schubert's final chamber work, the String Quintet in C major (D. 956, Op. posth. 163) is sometimes called the "Cello Quintet" because it is scored for a standard string quartet plus an extra cello instead of the extra viola which is more usual in conventional string quintets. It was composed in 1828 and completed just two months before the composer's death. The first public performance of the piece did not occur until 1850, and publication occurred three years later in 1853. Schubert's only full-fledged string quintet, it has been praised as "sublime" or "extraordinary" and as possessing "bottomless pathos," and is generally regarded as Schubert's finest chamber work as well as one of the greatest compositions in all chamber music.
The string quintet was composed in the summer or early autumn of 1828,: 183 at the same time as Schubert composed his last three piano sonatas and several of the Schwanengesang songs. Schubert completed it in late September or early October, just two months before his death. Schubert submitted it to one of his publishers, Heinrich Albert Probst, for consideration, saying that "finally I have written a quintet for 2 violins, 1 viola, and 2 violoncelli ... the quintet rehearsal will only begin in the next few days. Should any of these compositions by any chance commend themselves to you, please let me know." Probst replied, asking only to see some of Schubert's vocal works and requesting more popular piano music. Even at this very late stage in Schubert's career, he was regarded as a composer who mainly focused on songs and piano pieces, and was definitely not taken seriously as a chamber music composer. The work remained unpublished at the time of Schubert's death in November 1828; the manuscript was sold to the Viennese publisher Diabelli by Schubert's brother Ferdinand shortly thereafter, but was neglected and indeed waited twenty-five years for its first publication in 1853. The manuscript and all sketches are now lost. The first known public performance occurred only three years earlier, on 17 November 1850 at the Musikverein in Vienna.