Influenced by the blues musician Eric Von Schmidt, Rowan traded his electric guitar for an acoustic and began to play the blues. He was also influenced by the folk sound of Joan Baez. In college, he discovered bluegrass after hearing The Country Gentlemen and The Stanley Brothers. He soon discovered the music of Bill Monroe, and with some help from banjo player Bill Keith, he was invited to Nashville to audition for Monroe. Accompanied by Keith, Rowan went to Nashville and was hired in 1963 or 1964 as songwriter, rhythm guitarist and lead vocalist of Monroe's Bluegrass Boys.Goldsmith 2004, p. 263–264. His recording debut as a "bluegrass boy" took place on October 14, 1966 and he recorded a total of fourteen songs with Monroe, including the classic "Walls of Time" co-written with Monroe, before his tenure ended in the spring of 1967.Rosenberg, Wolfe 1991, p. 27–28.
