Francis O'Neill (1848-1936) was born in Tralibane, County Cork, Ireland. He excelled as a student in local schools, and went to sea in 1865, working on a number of ships and travelling widely over the next few years.

After working as a shepherd in the Sierra Nevada and qualifying as a teacher in Missouri, O'Neill married Anna Rogers, also an immigrant from Ireland, and settled in Chicago where he joined the police force in 1873. He distinguished himself in the police force, rising through the ranks and becoming Chief of Police from 1901 to 1905.

Throughout his career, he was involved with Irish music, playing the flute, the fiddle and the uileann pipes, and over time he became increasingly interested in collecting, studying and preserving Irish tunes. He collaborated with fellow Irish immigrant, James O'Neill (1863-1949), also a police officer, who transcribed many of the tunes that were collected. Francis O'Neill published O'Neill's Music of Ireland in 1903. This contained 1,850 melodies, a larger collection than any published before. He subsequently published five more music collections and two other books, Irish Folk Music: A Fascinating Hobby (1910) and Irish Minstrels and Musicians: with numerous dissertations on related subjects (1913). O'Neill continued to live in Chicago after his retirement in 1905, and remained very active in the Chicago Irish music community.

His personal library, built over his lifetime, consisted largely of Irish historical and antiquarian works (his "Hibernicana") and a collection of music books. In 1931 he donated this library to the University of Notre Dame.