Continuing my tendency to read way too much into things:
I was thinking about highwaymen, and listening to Metallica’s version of Whiskey In The Jar, and it occurred to me that I’d heard some Irish folksingers performing it once, so maybe it really is an Irish folk song. Did some quick and dirty research with Google and found dozens of variants. There are several differences between the variants, breaking down into two basic variants with a ton of sub-variants, with various small details differing between them. For instance, the girl’s name is sometimes Jenny and sometimes Molly. But other things are nearly constant. For instance, in almost all of them, the antagonist (the guy the narrating highwayman stole from, and who eventually brings the highwayman down) is named Captain Farrell. (Sure, there are variants in which he’s Colonel Farrell or even Captain Pepper, but 9 times out of 10 it’s Captain Farrell.)
Was there a real Captain Farrell who was placed into the song’s story, or is it just that someone made up a name to rhyme with “shot him with both barrels” and it stuck?
(A Google search on his name comes up with the lyrics to the songs some more, so I’m thinking the answer is (b), but you never know.)
Putting a few different search criteria into Google came up with lots of, well nuthin’ much, but this link seems to confirm your suspicions that there isn’t a lot to it. The lyrics are very changeable.
Not much to ad, but Thin Lizzy did a rendition of Whiskey in a Jar . Thin Lizzy, or at least lead singer Phil Lynott, was Irish. You might have heard it.
Thin Lizzy’s version is what Metallica covered. And in a fit of curiosity late last night I actually did small research on different variants of the song. I knew that sometimes such songs were based on real people, and I wondered if that were the case here. Thanks for helping me figure out that the answer is “nope, probably not.”
Go to the Mudcat Cafe (Folk & Blues music site) - http://www.mudcat.org/threads.cfm - and do a search or post a question. You may get more info or possibly a definitve answer.