O Heffernan - Irish / Ua hIfearnain. A Heberian Dal gCais Sept / Family branch, who had their territory originally centered on Corofin in Co. Clare in the north - west of Thomond / Tuaiscert Mhumhain / Northern Munster under the O Quinns, who were the Chiefs of Muinntear Ifearnain. They were also on the Co. Limerick and Co. Tipperary border in the Munster Province, where they were Chiefs also of Owney Beg in their own right. Ancestors: *94.Ifearnan, *93.Corc, *92.Aengus / Oengus “Ceann Aitin” / "Cinnaitin," *91.Cas (Dal gCais) the King of Thomond.

O Heffernan or O Hiffernane - Irish / Ui hIfearnain / Clann Crecain. An Irian Laeghis Ui Mheic Uais / Mheic Fhiodh "Bhuidhe" of Breagh (Muintir Fhiodhbhuide) Sept / Family branch, who were kinsmen to the Mac Evoys / Mheic Fhiodhbhuide who had their territory at Mountrath in Co. Laois in the mid - north - west of Southern Leinster. They were Kings in Co. Westmeath in the south - west of Northern Leinster, and nearby in Co. Laois in the mid - west of Southern Leinster, and Co. Armagh in the south - east of the Ulster Province. Their territory was initially at Moygoish in Co. Westmeath, from which they moved to the south - west as one of the "7 Septs of Leix," controlling the area of Mountain Rath and Raheen in Co. Laois. In their kingdom there in Leix / Co. Laois, they existed along with the O Deevys, the O Dowlings, the O Kellys, the O Lalors and the O Mores after the Anglo - Norman Invasion in the 12 Century AD. Their initial alliance had previously begun after the 3rd Century AD, when the ancestor of the Irian O Mores, came into Co. Laois from the Ulster Province led by *69.Laoighseach "Cean Mor," a son of *68.Conall "Cearnach" - of the Victories, the leader of the Red Branch Warriors of Ulster, who was a contemporary of Cuchulainn (Co. Laois is named for *69.Laoighseach.) He assisted 86.Cu "Corb" the direct ancestor of the Heremonian Ui Laoghaire U Lughaidh Cu Corb Kings of Leinster, to drive the men of Munster Province out of that area there in Mogha's Half. They became the sub - Kings there, and they held together all through the English persecutions and six ethnic and religious rebellions under Elizabeth 1st, until they were finally dispersed by the English and relocated elsewhere. In the early 17th Century AD the leaders of all of the Families there were transported once again, by the English by force, to Co. Kerry in the south - west of Desmond / Southern Munster, along with the other members of the "7 Septs of Laois," and their territory was transplanted with English Planters. Ancestors: *62.Rory "Mor" the 86th King of Tara / Erinn (Clann Rory), *37.Ir (Irians).

O Heffron or O Hefferan or O Haveran - Irish / Ua hEimhrin. A Heremonian Ui Cobhthaigh Dal Cuinn "Northern" Ui Niaill Sept / Family branch, who had their territory in Co. Mayo in the mid - west of the Connacht Province. O Haveran was used as a variant in the Ulster Province. See also - O Heerin. Ancestor: *87.Niall of the Nine Hostages the 126th King of Tara / Ireland (Ui Niall).

O Hegan. A Heremonian Ui Cobhthaigh Dal Cuinn Colla da Crioch Airthir Ui Niallain Clann Cernaich Sept / Family branch, who had their territory at Oneilland East and West, in Co. Armagh in the south - east of the Ulster Province. Especially see - O Hagan,

O Hegarty - Irish / Ua hEigceartaigh - eigceartaigh / unjust. A Heremonian Ui Cobhthaigh Dal Cuinn  "Northern " Ui Niaill Cenel nEogain Sept / Family branch, who had their territory between Co. Derry and the adjacent territory in Co. Donegal in the north of the Ulster Province. Ancestors: *88.Eogan the 1st King of Aileach (Cenel nEogain), *87.Niall the 126th King of Tara / Ireland (Ui Niaill).

O Hegarty - Irish / Ua hEigceartaigh - eigceartaigh / unjust. A Heberian Eoghanacht Sept / Family branch, who had their territory in the Munster Province. Ancestors: *85.Eoghan "Mor" (Eoghanachta), *84.Ailill "Oluimm" the 1st King of Munster.

O Hegney or O Hegeany or O Heagney or O Heaney - Irish / Ua hEignigh. (38 variations) A Heremonian Ui Cobhthaigh Dal Cuinn Colla da Crioch Siol Daim Argait (Ui Cremthainn) Clann Lugainn Sept / Family branch, of the Maguires, who had their territory initially in the kingdom of Orghialla / Oriel in Co. Armagh, Co. Monaghan in the south of the Ulster Province, who then migrated into Co. Fermanagh in the south - west of the Ulster Province, were they were Kings and Chiefs. Especially see - O Heany.

O Hehir or O Hegher - Irish / Ua hAichir - aichir / bitter / sharp. A Heberian Eoghanacht Ui Fidgeinti Sept / Family branch, of the Ui Cormaic Tuath / Family region, who at one time had their territory in Co. Clare in the north - west of Thomond / Tuaiscert Mhumhain / Northern Munster. As Eoghanachta their original territory had been in the Barony of Kenry in Co. Limerick in the mid - north - west of the Munster Province. Around 1100 AD they were the Chiefs of Magh Adhair, Ui Cormac and Ui Flanchadha, and their territory then was in the Barony of Islands from the Callan Mountains to the town of Ennis bounded on the north by the Breintir Fearmaic and by the Cenel Cuallachta, on the east by the river Fergus that separated them from the Ui Caisin and the Tradraighe, on the south by East Corcabascin and on the west by the Ui Braicin. Later on they were driven westwards by the Mac Namaras the Heberian Dal gCais Ui Caisin Clann Cuilean Lord Marshalls for for the Heberian Dal gCais Ui Bloid Ui Turlough Ui mBriain. Ancestors: *Eoghan of Orior Cliach, *90.Brion, *89.Fiachu "Fidgennid," *88.Maine "Munchain," *87.Ailill "Fland Bec," *86.Fiachu "Mullethan" the 1st King of Southern Munster, *85.Eoghan "Mor," (Eoghanachta) *84.Aillill "Oluimm" the 1st King of Munster.

O Heir. A Sept / Family branch, who had their territory in Co. Armagh in the south - east of the Ulster Province, where they were Chiefs.

O Helehan - Irish / Ua hAoilleachain. Used as a variant for O Whelahan, which see - faoilleach / joyful. A Sept / Family branch, who had their territory in Co. Waterford in the south - east of the Munster Province.

O Helly. Used as a variant for O Hely, which see, in and around Co. Sligo in the north - west of the Connacht Province.

O Hely. A Sept / Family branch, who had their territory in Co. Limerick in the mid - north - west of Thomond / Tuaisceart Mhumhain / Northern Munster. See also - O Healy.

Hempenstall or Hepenstal. English toponymic origins. They came from Yorkshire in the 17th Century AD, and were in Co. Wicklow in the south - east of Southern Leinster.

Hemphill. Scottish toponymic origins. They came from Ayrshire, and have been in Ireland since 1630 AD. They were in Co. Offaly in the north - west of Southern Leinster in the 18th Century AD, and are now also in Co. Derry in the north - east of the Ulster Province.

O Henaghan or O Henihan - Irish / Ua hEineachain / Ua hEanachain. A Heremonian Ui Cobhthaigh Dal Cuinn Ui Fiachrach Sept / Family branch,  who had their territory in Co. Mayo in the mid - west of the Connacht Province. See also - Bird. Ancestors:*87.Fiachra the original 2nd King of Connacht (Ui Fiachrach), *86.Eochy "Mugmedon" the 124th King of Tara / Ireland.

O Henchy or O Hinchy - Irish / Ua hAonghusa. O Hennessy used elsewhere. (Descended from *Angus / Oenghus.) Ua hInse now used incorrectly. A Heberian Dal gCais Sept / Family branch, who had their territory in Co. Clare in the north - west of Thomond / Tuaiscert Mhumhain / Northern Munster. Ancestors: *Angus Ua hInse, *91.Cas (Dal gCais) the King of Thomond.