Fermanagh - Irish Place Names

Patrick Weston Joyce
1923

Fermanagh; so called from the tribe of Fir-Monach, (The Topographical Poems of O'Dugan and O'Heerin), the men of Monach, who were originally a Leinster tribe, so named from their ancestor, Monach, fifth in descent from Cahirmore, monarch of Ireland from A.D. 120 to 123.