Brn,
I asked this question also, the answer I got is that no one really knows for certain when it came to be, but most people think it started during the Famine.
I found this thread on the net so it needs to be verified for accuracy, but at least it sounds good:
http://www.takeourword.com/TOW156/page2.html It is the third or fourth question down.
From J. David Neher:
A boxty is a traditional Irish potato pancake or roll and I'm assuming that that it's an English word. I've looked in your site, emailed Irish (i.e. in Ireland) pubs, restaurants and government agencies to no avail. Can you help.
Well, we're a bit cautious of rushing in where the Irish government fears to tread, but here goes.
Yes, boxty is an English word but most dictionaries, if they mention it at all, simply say that its origin is Irish without divulging the precise details. Our Irish-English dictionary tells us that bacstaid is "bread made of the raw pulp of potatoes; a boxty". No etymology is given but we assume that it is related to the words bacail, "the act of baking", bacalaide "a baker", and bacus, "a bakery". As the latter is clearly a Hibernian version of bake-house, it is quite likely that all these words have their origin in the English word bake.
(Message edited by do_chinniúint on November 10, 2007)
(Message edited by do_chinniúint on November 10, 2007)