The influence of the musical theatre on the Irish folk song tradition could fill a book let alone a Mudcat thread post.

I've been looking at Irish-American songs from vaudeville theatres and the (earlier) concert saloons for a few years now. Some New York stage songs that entered tradition include "Finigan's Wake," "Muldoon, the Solid Man" and "Get Up, Jack, John Sit Down." They are of 1860 to 1885 vintage.

Not all the traditional singers I've met think of themselves as static entities, meaning they are very open to learning new songs from outside their communities. Folk songs spread by singers from one place learning songs from another place. Sometimes that happened because people went away to work... sometimes travelers such as vaudevillians, ballad sellers and laborers brought new songs to other areas... sometimes people got songs from the printed page.

The Clancys were all actors as much as singers. They were looking for songs that would get the desired response from an audience. Songs did not have to pass a purity test to get into the Clancy's repertoire.

All the best,
Dan