Mac Harg. A Sept / Family branch, who had their territory in Co. Tyrone in Central Ulster. An earlier form of Maharg. See also Mac Ilhagga.

O Hargadan - Irish / Ua hArgadain - argat / silver / shining. A Sept / Family branch, who had their territory in Co. Sligo in the north - west of the Connacht Province. Hardiman now mostly used in Co. Galway in Southern Connacht.

Hargan. Used as a variant for Horgan, which see, in the Ulster Province.

O Harkins or O Harkin or  O Harkan - Irish / Ua hEarcain - earc / red. An Erenagh Sept / Family branch, who had their territory at Inishowen in Co. Donegal in the north - west of the Ulster Province. Not connected to Arkins in Co. Clare in the north - west of the Munster Province.

Harland. English toponymic origins. They came from Yorkshire and Devon and have been in Ireland since 1664 AD in Co. Armagh in the south - east of the Ulster Province.

Harley. English origins. Used as a synonym for Harrily, which see. Some changed to Hurley in the west of Co. Cork in Southern Munster.

Harman. Used as a variant for Hardiman, which see.

Harman / hereman / warrior. English origins. They were in the Leinster Province. Harmon used in Co. Louth in the north - east.

O Harnett or O Hartnett - Irish / Ua hAirtneada. A Sept / Family branch, who had their territory in the south - west of the Munster Province. Hartnett used in Co. Cork in Southern Munster. Harnett used in Co. Limerick in the mid - north - west of Munster. Harnedy also used as a variant.

O Harney - Irish / Ua hAthairne - athardha /' paternal. Originally anglicized as O Haherny and later also as O Hartney, which is also confused with O Hartnane. They were a Sept / Family branch, who had their territory in Co. Roscommon in the east of the Connacht Province, but are now also nearby in Co. Tipperary in the north - east of the Munster Province. They were also Chiefs in Co. Kerry in Iar Mhumhain / South Western Munster.

Harold or Harailt or Haroid. Danish Norse origins. In Ireland before the Anglo - Norman Invasion in the 12th Century AD in  Co. Dublin in the north - east of Southern Leinster and in Co. Limerick and Co. Clare in the north - west of the Munster Province.

O Haroughten. An Erenagh Sept / Family branch, who had their territory in Co. Roscommon in the east of the Connacht Province. See also Harrington.

Harpur or Harper / le Harpur (the harper). They were in Mid - Leinster Province in the 13th Century AD. Harpur now found in Co. Wexford in the south - east of Southern Leinster although it is sometimes spelt Harper there, also Harperstown is there.

Harper. English origins. They came into Ireland during the Confiscation of the 3,500,000 acres in the Ulster Province of the Heremonian Ui Cobhthaigh Dal Cuinn "Northern" Ui Niaill territories there and the Foreign non - Catholic Plantations there

O Harraghan - Irish / Ui hArraghain. An Irian Laeghis Ui Laoighis Sept / Family branch of the O More / O Moore / Ui Mordha, who had their territory in Co. Laois in the mid - north - west of Southern Leinster. Especially see - O Harrigan.

O Harraghan - Irish / Ua hArchain. A Sept / Family branch, who had their territory in Co. Leitrim in Northern Connacht.

O Harrahill - Irish / Ua hEarghail. A Sept / Family branch, who had their territory in Co. Clare in the north - west of Thomond / Tuaiscert Mhumhain / Northern Munster and are now also in Co. Waterford in the south - east of Munster.

O Harran or O Herron - Irish / Ua hEarain - earadh / dread. Originally a Sept / Family branch, who had their territory in the Heremonian Ui Cobhthaigh Dal Cuinn 3 Colla kingdom of Orghialla - Oriel in Southern Ulster who are now in Co. Donegal in the north - west of Ulster Province. Not connected to Haren in Co. Clare in the north - west of the Munster Province.

O Harrigan or O Harraghan or O Harahan - Irish / Ui hArraghain. An Irian Laeghis Ui Laoighis Sept / Family branch of the O More / O Moore / Ui Mordha, who had their territory in Co. Laois in the mid - north - west of Southern Leinster. Kinsmen to O Brophy / O Brofie / Ui Broithe, O Cashin / O Kissane / Ui Casain, O Deegan / Ui Duibhgainn, O Doran / O Dorrian / Ui Deoradhain, O Dowling / Ui Dunlaing, Mac Gahan / Mac Geehan / Mageehan / Mheic Gaethain, Mac Keady / Mac Keadie / Mac Keddy / Mac Keedie / Mac Keedy / Mackeady / Mheic Ceadach, Ui Liathain, O Lalor / O Lawlor / Ui Leathlobhair, Mac Lee / Mac Lea / Ui Laoidhigh, O Swords / O Sord / O Sourdes / O Suard / Ui Suaird. Ancestors - *Fachtna, *Milige, *Bran, *Eircc "hUbulchind," *Felim / Feidlimid mheic Finnchad, *78.Fiachach "Uanchind, *77.Daire, 76.Rossa, *75.Ogomain, *74.Fergus, *73.Muleist, *72.Fachtna, *71.Milige (Ui Baccan), *70.Intait, *69.Lugdach "Loichsi" / Laoiseach "Ceann Mor" the ancestor of the O More / Moore / Siol Morda Sept in Co. Laois (named for him) in the north - west of Southern Leinster who were among the ”7 Septs of Laois, *68.Conall "Cernach" - of the Victories the leader of the Knights of the Red Branch of Ulster who is the direct ancestor of the Mac Guinness, Mac Gowan and many other Irian Families in the Ulster Province and the Connacht Province. (He was a contemporary of Cuchulainn), *67.Aimhirgin "Larghiunach," *66.Cas, *65.Fachtna, *64.Cathbladh, *63.Cionga,  *62.Rory / Ruaidri “Mor” - the Greater who died in 218 BC as the Irian 86th King of Tara / Erinn (Clann - na - Rory,  *37.Ir (Irians).  

O Harrigan. In the south and the west of the Munster Province it is usually used as a variant for O Horgan, which see.

O Harrihy or O Harhoe - Irish / Ua hEarchaidh. A Sept / Family branch, who were  originally O Harahy, who had their territory in the Barony of Banagh in Co. Donegal in the north - west of the Ulster Province. Harvey used in Co. Fermanagh in the south - west of Ulster. Horohoe - Irish / Ui hEarchadha used as a variant in Co. Mayo in the mid - west of the Connacht Province, which see. Also changed to Harris and Harrison.