He settled in the Falls Road area of Belfast where he lived with his sister in a house at 43 Cavendish Street.
He was a stage manager of the Ulster Theater and would even become involved with the IRA, likely a member of military council.
He would return to Ireland after raising $100,000 for victims of the Belfast riots through White Cross.
Known for his dandified dress style, Cathal remained a bachelor his entire life.
[3] O'Byrne's poem "A lullaby" from " Lane o' the Thrushes" was set to words by an Irish composer of the same time, Hamilton Harty, in his "Six Songs of Ireland".