Life in the United States was hard for him. He spoke no English and people there did not know his music. He had left all his scores behind. However, he worked hard and the famous conductor Sergei Koussevitsky asked him to write a symphony. His music still sounded very Czech. After World War II he very much wanted to go back to his own country, but the communist government made that impossible. He had a bad fall and it took him years to recover properly. He taught at Princeton University, then he retired to Nice in France. He died of cancer in Basle.