In 1875, when the 34-year-old Dvorák composed his second String Quintet, he was becoming a prominent figure in Prague musical circles. He had spent his youth cultivating the "new" style of Liszt and Wagner in the face of opposition from conservatives in the musical establishment, and then rejecting that style himself and developing the quintessentially Bohemian voice for which he would become known. Nothing symbolized the change more than his opera King and Charcoal Burner, which he composed in his German phase. It was put into rehearsal at the Prague Provisional Theater in 1873, but had proven too difficult to perform and was dropped. Instead of making the hard parts easier, Dvorák threw the score out and composed an entirely new opera to the same libretto, describing the new work as "national rather than Wagnerian."

Embracing Bohemian nationalism would ordinarily have meant that he was abandoning prospects of becoming prominent internationally in favor of becoming a local favorite son, but it turned out to be the key to widespread fame. Dvorák's music won him Austrian state artist stipends in 1874 and 1875, but more important than the stipends themselves was that it attracted the attention of Brahms, who was on the selection jury. Though Brahms was only eight years older than Dvorák, he had been famous for two decades and had great influence, which he used to push Dvorák's career, getting him a publishing contract with the prestigious Simrock firm.

The Quintet in G that Dvorák completed in 1875, and called Op. 18, was composed for a chamber music competition sponsored by a Prague organization named the Artistic Circle. It won the prize and lavish praise from the jury for its "distinction of theme, technical skill in polyphonic composition, and mastery of form," and "knowledge of the instruments." It consisted of five movements: the four we hear tonight plus an Andante religioso that had been adapted from a string quartet and would later become the Nocturne for Strings, Op. 40. Simrock published the four-movement work, now considered the definitive version, as Op. 77 in 1888. (Simrock often published older Dvorák works with deceptively high opus numbers, which greatly annoyed Dvorák, who did not want the public mistaking his youthful works for mature ones.)

The addition of the double bass to the standard quartet adds sonority and a sense of space, which greatly contributes to the open-air quality of the work, particularly in the first movement. Dvorák, who had a Schubertian gift for melody and was often profligate with his themes, here makes less do more in the outer movements. Small motifs are combined into long sequences, repeated while the harmony changes around them, or pitted against one another in counterpoint. The Scherzo and the Finale actually begin with (and are built to a great extent from) the same five notes, though the effect is drastically different because both meter and key are different. Even in the Poco andante, where Dvorák the magical melodist creates a movement of sweet warmth, a few phrases do most of the work.

The Quintet is not so different in this respect from baroque music. Vivaldi, for example, would have been right at home creating musical paragraphs from short phrases, but Vivaldi and his colleagues wrote movements that were significantly shorter than the extended sonata structures of the 19th century. It says much about Dvorák's ability to develop his material that the music never becomes tedious regardless of how much repetition goes into its construction.

— Howard Posner has also written program notes for the Los Angeles Baroque Orchestra, the Coleman Concerts, and the Salzburg Festival.