This paper explores the role of classical music in the construction of nationalism in the twentieth century. It takes its point of departure in the Danish composer Carl Nielsen and analyses competing interpretations and receptions of his works. The paper seeks to move beyond the single case study. Hence, it includes three additional cases: the Soviet composer Dimitry Shostacovich (particularly the reception of his 5th Symphony); the position of Paul Hindemith in the Third Reich; and finally the development in Aron Copland's oeuvre. In so doing, it aims to clarify the relationship between classical music and nationalism.