COOLAHAN Family History
Recorded as Mac Cuolahan, O' Cuolahan, Cuolahan, Coolahan, Coolican and others, this is an Irish surname of great antiquity. It derives from the medieval Gaelic Mac Culachain or O' Culchain, both in effect meaning the male descendant of the proud one. Who the "proud one" was is unclear, but the great majority of Irish surnames do originate from a nickname for the first chief of the clan. The Mac name is often confused with Mac Coughlan mainly because in the past the Mac Cuolahans and the Mac Coughlans shared ownership of the parish of Lusmagh in the barony of Garrycastle, County Offally.