Paul Tietjens (22 May 1877 – 25 November 1943) was an American composer of both popular and serious music in the first half of the twentieth century. His greatest success came when he composed music for the 1902 stage adaptation of L. Frank Baum's The Wizard of Oz. Tietjens was born in St. Louis (as was, coincidentally, Baum's other main composer, Louis F. Gottschalk). He followed a course of study in classical music, and debuted as a piano soloist with the St. Louis Symphony at the age of fourteen. He later studied in Europe with several teachers.