Though Engle was primarily a farmer, he is best known for his work as a musician and songwriter. The most famous of Engle's work is The West Virginia Hills which eventually became one of West Virginia's state songs. The song was written based on Rev. David King's poem of the same name. For the song, Engle composed the music and wrote the lyrics for the chorus. The song was written in 1885 and Engle secured a copyright for his music a year later. The song was included in The West Virginia Singer in 1913. From 1960 to 1961, some edits to the song and music were completed by C. Buell Agey of West Virginia Wesleyan College in an attempt to create a definitive version. This final version of the song was officially adopted as one of the state's songs following the passage of a 1961 resolution. Engle also wrote Take the World for Christ and My Country Home.
Engle died of apoplexy at his home in Braxton WV in 1933 and was buried in a small cemetery on the family's property.