[Surname] Re: SURNAME DONNELLY ETHNIC BACKGROUND IRISH DUBLIN
in reply to a message by SARA DONNELLY
Donnelly is explained on this site under "Irish names". The explanation is, as far as my knowledge goes, accurate. I would add that the name is associated historically with the County Tyrone where there is a place now called Castle Caulfield, which was once called Ballydonnelly, "O'Donnelly's townland".