Schloss was born in Saarlouis, Germany on 3 May 1902 and studied composition at the Hoch Conservatory in Frankfurt. He continued his education in Vienna under Alban Berg, for whom the young pupil emerged as a competent and trustworthy assistant, editor and friend. Schloss oversaw the editorial work on Berg’s opera Wozzeck and his Lyric Suite for string quartet. During this time, Schloss composed several significant works, including his first string quartet, a sonata for piano, and a requiem for chorus and percussion, for which he won the Emil-Hertzka Gedächtnis prize in 1933. By the late 1930s, Schloss’s Jewish heritage put him at great risk under the Hitler regime. After being briefly interned at the Dachau concentration camp in 1938, Schloss immigrated to Shanghai. In 1948, he left China for the United States, settling in Belleville, New Jersey and attaining citizenship in 1954. In spite of his European success, Schloss was unable to secure a teaching position or editorial work in his new homeland. While his works continued to be performed with support from long-time friend Karl Steiner, Schloss continued to compose until his death on 26 October 1973 at age 71.