[1][2][3] In the 1920s Galway-born accordionist Peter Conlon (c 1885-c 1954) gained prominence in the United States, recording on the 1-row extensively beginning about 1917.
Around 1947, Boston-born Joe Derrane (under the tutelage of Jerry O'Brien) upgraded from a 10-button to a chromatic 2-row instrument and recorded a number of 78rpm albums.
Uniquely, O'Brien and Cooley imitated the violin or flute style of playing, a slow unaccented smooth performance.
It was completely divorced from the tradition of Irish accordion playing in the States which took into consideration the mechanics of the instrument.
This was augmented by the legendary accordionist, songwriter, singer and Irish football star, Dermot O'Brien, who emigrated to the United States in 1983.