O'Hara
An Irish surname from the Gaelic O’Hara line, tied to an old noble sept recorded in medieval Ireland.
The #1,660 most common surname in the United States (2010 Census) — about 1 in every 14,221 Americans shares it.
Etymology
O'Hara is the anglicized form of the Irish Gaelic surname O hEaghra, usually explained as meaning 'descendant of Eaghra.' The older dictionary evidence supplied here treats it as a noble Irish sept name and records an early medieval bearer, Donagh O'llara, in the year 1023. The exact sense of the personal name Eaghra is less certain in older scholarship, so the safest explanation is that it is a descent-name rather than a transparent occupational or descriptive term.
History
The name is associated with an ancient Irish family whose power was centered in what is now County Sligo, in territory once described as including parts of the baronies of Leney, Costello, and Gallan. Historical notices place the sept among the older Gaelic families of the northwest, and the surname remains common in Ireland and in Irish diaspora communities, especially in the United States. Later spellings often dropped the apostrophe, producing OHara.
Origin
Regions
Variant spellings
Fun fact
The historical notice cited in the older source says the family was already notable by the early 11th century, making it one of the older recorded Irish surnames in that tradition.
From the historical record
“government." D'Alton. OHARA. A noble sept dating back at least to the year 1023, when the death of Donagh O'llara is recorded by the Four Masters. Their territory comprised the present barony of Leney, with parts of those of Costello and Gallan. D'Alton. O'HEA. An ancient family of the county of Cork, whose chief…”
— Patronymica Britannica: a dictionary of the family names of the United Kingdom