Born in Wisconsin, Kelley studied in Chicago before moving to Stuttgart in 1876 to study for four years. Upon his return to America, he moved to San Francisco, continued his performance career at the organ and piano, taught, and became interested in Eastern music. One of his most famous pieces from this period is his Aladdin, a suite for orchestra which utilized elements of Chinese music.

Kelley moved to New York, where he married and worked as a conductor of light opera while continuing his other activities, including composition. After a brief time back in San Francisco as a music critic for the San Francisco Examiner, he returned to New York. In 1901, he taught for one year at Yale University, replacing Horatio Parker while he was on sabbatical. Kelley taught in Berlin from 1902 to 1910 before returning the United States and eventually took a post at the Cincinnati College of Music, where he remained form 1911 until 1934. He published two books during this time: Chopin the Composer (1913) and Musical Instruments (1925).

As a composer, Kelley was a Romanticist, much like other European trained Americans such as Horatio Parker, Arthur Foote, and George Whitefield Chadwick. Kelley was also devoted to American music and increasing its popularity in Europe.

–Christie Finn Source: New Grove Dictionary of Music and Musicians