Born in Philadelphia, Rex Isenberg (b. 1987) began his musical life as a jazz pianist and vocalist before applying his talents as a composer. Characterized as "timeless", "infectious", and "inviting" (Herald Times, IN), Isenberg’s work blends a diverse array of styles and frequently draws upon historical events and texts, imbuing them with renewed meaning for contemporary audiences.

Isenberg served as Composer-in-Residence for Choral Chameleon in 2016-17 and as a Composition Fellow at Norfolk Chamber Music Festival in 2015, and held residencies at the Banff Centre for Arts and Creativity in 2017 and Virginia Center for the Creative Arts in 2011. He has been commissioned by the American Viola Society, Cantori New York, Manhattan Saxophone Quartet, and others. His music has been performed and recorded by JACK Quartet, MIVOS Quartet, NOTUS Contemporary Vocal Ensemble, Cecilia Chorus of New York, Cantori New York, Grace Chorale of Brooklyn, St. Olaf Cantorei, percussionist Ian Rosenbaum, and violists Jessica Meyer and Miranda Cuckson. He has also collaborated with Tony winner Stephen Spinella and Tony nominees Kathleen Chalfant and Paul Hecht, who were featured narrators on his concert-length oratorio, Messiahs: False and True, in 2015, 2016, and 2018 respectively.

Isenberg studied composition with Richard Danielpour, Reiko Füting, Kathryn Alexander, Michael Klingbeil, and Missy Mazzoli. He holds a Masters of Music and a Doctorate of Musical Arts in Composition from Manhattan School of Music and a Bachelor of Arts in Music from Yale University. While at Yale, Isenberg was a member of The Yale Whiffenpoofs, composing several arrangements which he performed with the group in 20 countries and 25 U.S. states, for audiences which included the U.S. Ambassadors to China, Lithuania, and Chile, the Consul General of Mexico, and Presidents George W. Bush and Barack Obama.

He currently resides with his husband Matt in Los Angeles. His work is published through ECS Publishing.