O'Keeffe was born in Glountane Cross (in the townland of Knockdown), Cordal, near Castleisland in County Kerry, the eldest of eight children from a musical family.
Cal O'Callaghan had emigrated to the United States as a young man and had picked up various contracts as a buffalo hunter on the Great Plains for railroad companies, as well as one logging in Ohio.
A fiddler himself, O'Callaghan is said to have worked with numerous Scottish immigrants who left major influences on him, among them tunes and technique.
[citation needed] He is supposed to have received some formal instruction of the fiddle at his father's request but it is unknown who his instructor was.
[citation needed] Upon graduation, he left for Glasnevin, Dublin, to train as a national school teacher (as shown on 1911 census return) upon his father's request where he learned some music theory.
[citation needed] Scollard emigrated to Chicago and did not return, and is supposed to have been happily married with no ill feelings toward O'Keeffe.
[citation needed] At this point, O'Keeffe attempted to take up as a cattle dealer, and found work as a clerk in Tralee before returning to teaching, this time of music.
He also composed a number of tunes including Johhny Cope, a six-part variation on a traditional Celtic melody.