Kerrigan
An Irish surname, usually treated as a reduced Anglicized form of an older Gaelic name such as Ó Ciaragáin or a related Ciarán-based form.
The #5,204 most common surname in the United States (2010 Census) — about 1 in every 45,985 Americans shares it.
Etymology
The surname Kerrigan is generally explained as an Irish Anglicized form built on a Gaelic personal name in the Ciar- family, often linked to Ciarán or to a diminutive such as Ciaragán/Ciarragán. In that tradition, the underlying root ciar means 'dark' or 'dusky,' so the name originally referred to someone with dark coloring or hair. The spellings Kerrigan, Kerigan, and related forms reflect later English spelling of an Irish name rather than a separate English source surname.
History
Irish surname lists place Kerrigan chiefly in Connacht, especially Mayo and Galway, and it appears in the Irish surname scholarship of the late 19th and early 20th centuries in that regional context. The name was carried into the diaspora through emigration, which helped spread it more widely in Britain, North America, and elsewhere. Spellings vary considerably, and some early writers grouped it with other Ciar- names, showing that the precise Gaelic original was sometimes uncertain.
Origin
Regions
Variant spellings
Fun fact
In one early Irish surname survey, Kerrigan is specifically noted in Mayo and Galway, hinting at a strong western Irish core area.
From the historical record
“1003 KERRIGAN. 1026 KING. 429. Layne. 54. Carigin.”
— Varieties and Synonymes of Surnames and Christian Names in Ireland