He was born on 21 August 1907 in County Meath to James F. O'Donnell, a hotelier, of Burtonport, County Donegal, and Bridget O'Donnell (née McDonnell). Raised in Burtonport, O'Donnell was educated at national schools in Meenmore and Meenamara, and at St Eunan's College in Letterkenny.
