Posted this on ancestry.com - just thought I'd post it here too.
Let it be noted that I'm a lazy genealogist. What I find is usually from the comfort of my recliner, with my laptop as my only resource.
There's been much ado about whether a Cornelius or a Bryan K. Gainer came from some mysterious place called Gainertown Ireland. No doubt someone came from Ireland, and no doubt, they migrated through Virginia to Allegany County Maryland (possibly now Garrett County), and from there, it appears of 4 children, 2 went to what is now Gilmer, and 2 went to what is now Barbour. There appears to have been much communication and intermarrying between the branches.
But where and what is Gainertown? I suspect that Gaynor is the typical spelling of the name in Ireland. Most of them SEEM to have been centered in Longford County, near Lough Gowna (a lake named after a calf).
Here's something about a "baronie" called Granard, I think from wikipedia in a Longford County History post.
Granard - Anciently this was part of a territory known as Cairpre Gabra, alias Corpre Tethbae, or North Teffia. The barony was formed from the territory of Clanshane (Granard, Abbeylara, and part of Colmcille parishes), and from the territory of Slewcarberie (Clonbroney and part of Colmcille parishes). Muintir Geradhain was located on the west side of Lough Gowna, where Ó Geradhain (Gaynor or MacGinver) is mentioned as lord here in the 11th century.
Granard Town - There is a town in the Granard Territory called Granard and sometimes Granard Town. Seems like Gainertown could be a corruption of Granard Town but of course this is just speculation. Has anyone been to Granard? Might be a good place to check out.
Here's more on the Gaynor surname which is probably already posted because I'm sure I've seen it somewhere. Maybe on facebook. :-)
Mac Fhionnbhair, chief of Muntergeran, is recorded as being on the west side of Lough Gowna in the present county of Longford. Muntergeran, a shortened anglicized form of Muintir Geradhain and the eponymous ancestor of the family of Gaynor or MacGinver was Fionnbhair (Finbar) Ó Geradhain, who was lord of that area in the eleventh century. A hundred years ago the normal anglicization was Maginver with the synonym Gaynor already coming into more general use. MacGinty found synonymous with Gaynor in south Ulster appears as a principal name in Co. Westmeath in the "census" of 1659. Westmeath and Cavan which with Co. Longford are the counties in which the name is chiefly found today. The prefix Mac becomes Mag, first in speech and later in the written word, so that Mag Fhionnbhair is now the normal form in Irish. Ó Geradhain is identified with Ó Géaráin, a Hy Fiachrach sept located in Erris (Mayo). This sept of Ó Géaráin seems to be almost extinct today. There was another sept of the same name, anglicized O'Gerane and later Geran, which is listed among the principal names in that county in 1659. This survives there today as Guerin. Some of our Guerins may be of different origin, Guérin being a French Huguenot surname