http://clanflanagan.org/bibliography/ancient.shtml
Flanagan, History & Ireland About the name "Flanagan"
The surname Flanagan is descriptive in origin, "Flann" meaning red or ruddy. Most sources suggest that it means "red-headed" though some suggest that it refers to a ruddy complexion. Several distinct families with the surname emerged in Ireland, arising in different locales, including the counties of Fermanagh, Offaly, Roscommon, Waterford, and Westmeath.
Spelling variations of the name include: Flanagan, Flanaghan, Flangan, Flanigan, Flannagan, Flannigan, Flanningan, Flanikin, Flanakin, Flanagin, Flanigin, Flenniken, Flannacan, Flannacain, and any of these prefixed with an O'. A Bibliography of source material covering the course of Irish history may be found at the World of Royalty's Irish Royalty page.
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