Martinů bade a temporary farewell to the symphonic genre with his Fifth Symphony. The sequence of one Symphony per year ended when he produced no such work during 1947. One could cite several possible reasons for the cessation, not least the serious accident of July 1946. Composition of any sort proved to be difficult for some months, and even had he intended to write a Sixth Symphony in 1947, it is unlikely that he would have found the strength to do so. On the other hand, the gap in his symphonic output may signify a feeling that for now he had achieved all he could in the form. Furthermore – and somewhat remarkably considering his achievements – his original disinclination towards the symphony seems to have persisted. Šafranek quotes the following lines from a letter Martinů wrote to Paul Sacher in 1946 while at work on the Toccata e due canzoni:

Given this frank distrust of the alleged demands of symphonic writing, Martinů’s desertion of the form seems less surprising than his production of five symphonies in as many years. When he next embarked on a large-scale orchestral work, in New York early in 1951, it was with the clear intention of writing something quite new; a work distanced from the earlier Symphonies not only chronologically but stylistically too.