Well, I'm curious about the contemporary paths these things take (latter 20th century to present), as well as earlier in history. Back in the broadsheet days, a song might exist in tradition, then be put on a broadsheet and that version spread about more than others. Similarly, in the age of electronic media, a recorded version propagates much more rapidly than any other.

I'm wondering if the currently extant versions all arise from the one on the 1961 Canadian recording, that maybe reached Ireland via Frank Harte's recording of it (but I don't yet have the date of his Daybreak and a Candle-end). Is that too much of a stretch?

The "begats" exist, but actually tracing them is not always possible, liner notes being what they are. We do have the advantage of having a lot of those people still around though. :-)

On the older history, there's more in the notes for the 1997 or 1998 cd by Bruce Kincaid, THE IRISH VOLUNTEER, Songs Of The Irish Union Soldier 1861-65.

He says:
The air (melody) is called "Happy Land Of Erin," and the song is one of only two on the album ever previously recorded, therefore having withstood the test of time. This version may have been written post-war, when the government began cutting back on the veteran's pensions, as the lyric might suggest. I have come across another lyric, called "The Son Of Erin's Isle," which judging from the phrasing and the fact that some of passages are identical, is clearly a variant of the same song, yet decidedly more positive toward the Irish involvement in the war. Its chorus reads: "Cheer up, boys, the time will come again, When the sons of old Erin will be steering, And to the land will go o're, They call Columbia's shore, Where there's freedom for the jolly sons of Erin."

~ Becky