Sowerby began composing at the age of ten years. His first violin concerto was performed in 1913 by the Chicago Symphony Orchestra. From 1917 to 1919 he worked in Chicago as a military bandmaster. From 1921 to 1924 he studied as Rompreisträger the American Academy in Rome. From 1925 he was a professor at the American Conservatory, where Robert Stewart, Gail Kubik, William Ferris, Florence Price, Ned Rorem, Norman Luboff, Maylon Merrill and Gerald Near among his pupils, in 1927, he became organist and choirmaster at St James 's Episcopal Church in Chicago.
For the cantata Canticle of the Sun, he received the 1946 Pulitzer Prize. In 1962, he was founding director of the College of Church Musicians at Washington National Cathedral.
He composed more than five hundred works, including five symphonies, two cello and two piano concertos, a violin and an organ concert, a symphonic poem for two pianos and orchestra, a classical concert for organ and strings, chamber music, several cantatas and anthems and an oratorio.
- Composer of classical music ( 20th century)
- American composer
- Pulitzer Prize winner
- Born in 1895
- Died in 1968