Havelock Nelson was born in Cork. He studied at Trinity College Dublin and the Royal Irish Academy of Music. He was one of the founders of the amateur orchestra, the Dublin Orchestral Players, in 1939. He joined the BBC in Northern Ireland in 1947, working as a conductor, accompanist and broadcaster. He was awarded an OBE in 1966 for his services to music.
He has written both original compositions and arrangements which include numerous chamber, choral and orchestral works. He is particularly associated with vocal and choral settings of Irish folk-songs.