John Brennan was friendly with the Sligo fiddle players James ‘Lad’ O’Beirne (1911–80) and Martin Wynne (1913–98), who were resident in New York and whose playing is featured on the discs. Lad O’Beirne, who had emigrated there in 1928, had a homemade acetate disc-cutting machine, and this was doubtless the original source of most of the recordings. Martin Wynne came to the United States in 1948, and seems to have made the first two of these recordings with an unknown pianist in London before emigrating. Lad O’Beirne accompanies Wynne on piano on the latter’s New York recordings. The New York-born fiddle player Andy McGann (1928–2004) is also to be heard on one of the recordings, in duet with O’Beirne on fiddle and accompanied on piano by Jerry Wallace (1929–91). All of these musicians were influenced by the famous New York-based Sligo fiddle player and recording artist Michael Coleman (1891–1945), as can be heard in the repertory and style on the discs.