Haslam (Dweller by the Hazels) English toponymic and locative origins. They were in Ireland in the Mid - 17th Century AD before the Oliver Cromwell Invasion and were in Co. Laois and nearby in Co. Offaly in the north - west of Southern Leinster.

Haslip. See - Heaslip.

O Hassan - Irish / Ua hOsain - os / deer. A Sept / Family branch, who had their territory in Co. Derry in the north - east of the Ulster Province. Not connected to either Hession or Hishon.

O Hassett - Irish / Ua hAiseadha. A Heberian Dal gCais Sept / Family branch, who had their territory in Co. Clare in the north - west of Thomond / Tuaiscert Mhumhain / Northern Munster. No connection with the Anglo Norman Blennerhassetts who were English Planters though some members of that particular family there in Co Kerry in the south - west of Munster Province used it to shorten their own name. Ancestor - *91.Cas (Dal gCais) the King of Thomond.

Hasson. English origins. They were in Co. Wexford in the south - east of Southern Leinster.

Hatch. English toponymic and locative origins. They were in Ireland in the 17th Century AD in Co. Meath in the south - east of Northern Leinster originally, but are now also nearby in Co. Louth in the north - east of Southern Leinster.

O Haugh - Irish / Ua hEachach. See Mac Caughey for derivation. A Sept / Family branch, who had their territory in Co. Clare in the north - west of Thomond / Tuaiscert Mhumhain / Northern Munster and known also as O Hough nearby in Co. Limerick in the mid - north - west of the Munster Province.

O Haughey or O Haffey - Irish / Ua hEachaidh. A Sept / Family branch, who had their territory in Co. Donegal and Co. Armagh in the Ulster Province. O Haffey used in Co. Armagh.

Mac Haughey - Irish / Ua hEachaidh. Anglicized as Mac Gaughey, which see.

O Haughian - Irish / Ua hEachaidhin. A Sept / Family branch, who had their territory in the east of the Ulster Province. Some changed to Hawkins an English name that is common in the south - east of Leinster Province. Cognate with O Houghegan.

Haughton. Used by the O Haughans, which see - Irish / Ui Eachain.

Haughton. Used by the O Haghtir / O Hoctor, which see - Irish / Ua Eachtir. A Sept / Family branch, who had their territory in Co. Tipperary in Ormond / Aur Mhumhain / North Eastern Munster.

Haven. They were in Co. Westmeath in the south - west of Northern Leinster where it was used as a variant for Heaven, which see.

O Havern or O Haveran or O Havron - Irish / Ua hAmhrain. Used as variants for O Heffron, which see.

O Haverty - Irish / Ua hAbhartaigh / Arbartach. May also be a variant for Faverty? a Sept / Family branch, who had their territory at Craughwell in Co. Galway in Southern Connacht where they were Chiefs.

O Havlin. A Sept / Family branch,  who had their territory in Co. Donegal in the north - west of the Ulster Province.

Hay / de la Haye / Le Heise. Anglo Norman origins. They were in Co. Wexford in the south - east of Southern Leinster. Now changed to Hayes.