Family History and Genealogy Resources by Surname
O'Donnell Surname OriginThe descendants of Donal, an ancient Irish family, who trace their descent through Donal to Niallus Magnus, the ancestor of the O'Neills, known as Nial Niagallach, Nial of the nine hostages. The O'Donnells ruled the territory of Tirconnell, for thirteen generations. See Donald
Source: An Etymological Dictionary of Family and Christian Names With an Essay on their Derivation and Import; Arthur, William, M.A.; New York, NY: Sheldon, Blake, Bleeker & CO., 1857.
O'Donnell Surname Meaning and Family Facts
There is more to O'Donnell family history than the origin of your surname:
A O'Donnell Family History Thought:
'If man cares not for his roots, then how can he care for his branches?' --Doyle M Davis