After four years of toil and numerous premieres, Martinů had built up an enviable position in the American musical world. Yet with the end of the war, his plan was to return to Prague, where he expected to be received with a new level of respect. Once in Prague, he knew things would be different personally. With the reopening of postal communications in August 1945, he learned of his mother's death the previous year and that the previous month, his best friend Stanislav Novák—who had dealt with unspeakable tragedies during the war— had also died.

In September 1945, he received a telegram from Vaclav Holzknecht (1904–88), then the director of the Prague Conservatory, asking if he would be interested in a teaching position in the master class for composition. Seeing his lifelong goal finally at hand, he replied right away that he would be prepared to accept such an offer and returned to New York City from Cape Cod to make plans. He anticipated that things would move quickly from this point forward, but he became discouraged as he received no further news. What he did not realize was that—as part of Nejedlý's house-cleaning measures as the interim Minister of Education and Culture— Holzknecht had been relieved from his position as conservatory director. Also contributing to the silence from Prague was the reorganization of the music education system, resulting in the launch of the tertiary level Musical Academy of Performing Arts (HAMU) the next academic year.

An anomaly in his career was the fact that, after returning to New York City, he took a five-month break from composing before beginning work on his Fifth Symphony in February 1946. By this time, he had received an offer to teach at Tanglewood for the coming summer, and—unwilling to jeopardize his musical standing in the United States—he accepted the offer. Now, to protract his residence in America, he needed to change his status from endangered intellectual to immigrant, which required him to exit and reenter the country. This he resolved by traveling to Quebec in March 1946.