Trust, but verify; or There goes 1/16 of my family tree

(Protip: Just jump straight to "verify." We can "trust but verify" on Cold War relations and Iranian nuclear deals, but not genealogy!)

I received the death certificate of my 2x great-grandmother, Mary King O'Hara, a couple weeks ago. I had wanted it for years, but had always put off jumping through the Department of Health's hoops. Big mistake.

A relative interested in genealogy had sent me Mary's presumptive birth record years ago, and I took it at face value. It was, of course, a real birth record, for a real person named Mary King, but it no longer seems likely that she was the correct Mary King. There goes 1/16 of my family tree!

Lesson learned. Always verify the research of those who have gone before you. (I always knew that I should check this particular piece of information, but took it as a "starting point" until I could do the research myself. Nothing lost but time, I suppose.) (Also, don't take online trees as gospel, either, because mine is out there and it's (at least) 6.25% wrong.)

I had for years operated under the assumption that Mary King's parents were Michael King and Bridget Hopkins, and that she was born in Claremorris, Co. Mayo, Ireland, but her death certificate puts her parents as Patrick King and Bridget Fadden. I'd like to confirm that with a birth certificate that matches, of course, but right now, I don't know where to look. I've contacted the relative who sent the first birth record to see why he thought that that Mary King was our Mary King. If it was, for example, because Mary (whom he knew as a child) had talked about her childhood in Claremorris, then at least that's a place to start. If it was just because the dates matched on an index search, then I have all of Ireland to search. I'm waiting to hear back from him.

I have Mary's death notice, and it does not include a place of birth.

Mary was born in the 1870s (3 December 1875, according to her death certificate), and the civil registration indexes available for free online in this time period do not include mother's maiden name. Otherwise, this could be a pretty easy search. Other than browsing the registers of every Catholic parish in Ireland at the National Library, I'm not sure how to find Mary's actual birth place and birth record and confirm her parents. I might have to stoop so low as to subscribe to RootsIreland, despite my serious misgivings about the service they offer.


What are your best suggestions for locating an Irish town of origin?