Bohuslav Martinů was attracted to string instruments literally since his early youth. As a fairly accomplished violinist, he had a natural inclination towards the string ensemble. This was also thanks to his friendship with Stanislav Novák, his classmate from the conservatory and later the soloist and concertmaster of the Czech Philharmonic Orchestra and the founder of several chamber music ensembles (including the Novák & Frank Quartet). Martinů’s oeuvre comprises not only seven string quartets, string trios, etc., but also String Quintet (1927) and String Sextet, H 224 (1932), which come from a period that was crucial to Martinů’s development. Beginning with String Quartet No. 2 (1925), Martinů contributed to the shaping of Neoclassicism in music in the 1920s. He freed himself from Romantic invention and compositional techniques and subordinated his compositional work to purely musical laws. Despite his creative achievements, he had to struggle to make a living as a composer. He entered various competitions, and in 1927, when he visited Prague in September to attend concerts given by the foundation of the wealthy American patroness Elisabeth Sprague-Coolidge, he was so inspired that the following week in Polička he composed String Quintet dedicated to this influential lady. He thus joined the ranks of composers such as Stravinsky, Honegger, Bartók and Schoenberg, whose works were sponsored (and paid for) by this patroness, who let them be presented by first-class performers on international stages.
Martinů established another contact with Mrs. Coolidge in 1932, when he submitted his String Sextet to the competition announced by her foundation. It was also composed very quickly – in one week in May 1932, this time in Paris. It is characterized by a disciplined structure and a distinct style combined with rich creative invention as well as sophisticated instrumentation. It was awarded first prize from 145 entries in the competition. According to the recollections of Martinů’s wife Charlotte, Martinů at first did not believe the information about being the winner, thinking it a joke played on him by his friends. The first prize was $ 1,000. “I think I’ll buy an upright piano now. The time is good because no one is buying anything, so they are selling on good terms,” he wrote home to Polička. Until then he had to work on borrowed pianos. The prize also brought him a great prestige: the String Sextet was premiered by the Kroll Sextet in Washington on 25 April 1933. It was such a success that the piece had to be repeated once again the same night. Here Martinů characteristically works with short thematic models, which he varies and develops. The String Sextet forms an organic whole, original and unique not only in its scoring. Paradoxically, it is the unusual combination of instruments that prevents it from being performed more often. At the request of the American Music Publishers (APM) in New York, Martinů added a double bass part to his String Sextet. This version, which allows for orchestral performance, was first heard in the United States in 1951.