On March 25, 1918, at the height of American involvement in World War I, United States Bureau of Investigation agents and Boston Police Department officials interrupted eminent Germanborn conductor Dr. Karl Muck during a private Boston Symphony Orchestra (BSO) rehearsal of Bach's Saint Matthew Passion on the eve of its premier Easter performance in the city, demanding that he step down from the podium. Symphony manager Charles Adams Ellis convinced the men to hold off until the rehearsal had concluded, which they agreed to do, strategically positioning themselves throughout the hall, impatiently waiting until the conductor had finished his work. Following the rehearsal, Muck was escorted to a nearby office where he was asked a series of questions before being removed from the hall and transported to Boston's Back Bay Police Station for a more intense interrogation. On April 6, 1918, after spending more than a week in the “iron cage” of the East Cambridge Jail, he was arrested as a “dangerous enemy alien” and accompanied by armed US Marshals onboard the westbound train to Fort Oglethorpe Internment Camp in Georgia, where he remained under surveillance for a year and a half. His Boston property and his savings were confiscated, and he lost his income, his position in society, and his freedom, before being deported in August of 1919. Muck was a very well-known figure in the United States at that time. He had been conductor of the BSO from 1906 to 1908 and again from 1912 to 1918. His musical pedigree was impressive. Action taken against him by the United States federal government seemed very shocking.

Karl Muck's life and legacy in America was entirely reshaped by World War I. His rise and fall occurred so quickly that little is known about him historically. One rarely hears his name today, and most Americans are unacquainted with this musical giant of the Romantic era. Muck was no spy, however, and patriotism represents only a fraction of the intrigue surrounding his treatment. Authors have occasionally written about Muck as a high-profile international musician who, in 1917, refused to conduct “The Star-Spangled Banner” at a Providence, Rhode Island, concert and therefore became a victim of anti-foreign sentiment.