He was a composer, a founding member of the Department of Music at UC Davis -- " the face of UC Davis Music for a half-century" -- and a member of the faculty of the University of California between his appointment in 1952 and his retirement in 1988.
And he was married to my my father's sister, Sylvia. Jerry always was one of the people I looked forward to talking to at Terrell family gatherings. A few years ago he sent me a CD of an opera he wrote about The Emperor Norton.
Here's a little bit about his music from his obit in The Davis Enterprise.
As a composer, Rosen left some 60 works of solo and chamber music, often including clarinet or saxophone, as well as works for voice and those of symphonic and operatic scope. His large-scale works for saxophone, including a Concerto of 1957 and a Quintet for Saxophone and Strings, 1974, attracted considerable attention, especially in Europe. His two operas, “Calisto and Melibea,” to a libretto by Edwin Honig (1979), and “Emperor Norton of the USA,” to a libretto by James Schevill (1999), were produced in the Main Theatre at UC Davis.
His major song cycle to a volume by the UC Davis poet Karl Shapiro, “White-Haired Lover,” was premiered in 1979; additionally he set poetry of Celeste Turner Wright, including “Campus Doorways,” composed for the inauguration of what is now the Pavilion of the Activities & Recreation Center (ARC), 1978; this was played again for the dedication of Celeste Turner Wright Hall in 1997. For the 75th anniversary of the campus in 1984, Rosen composed the University Fanfare that continues to be heard at the start of each commencement ceremony.
Rest in peace, Uncle Jerry.