[1] The son of Richard MacDonnell, he was born in Harbour Main and was educated at Saint Bonaventure's College, at the National College of Ireland in Dublin and at King's Inns in Dublin.
MacDonnell taught school in Torbay before going to Ireland to continue his education.
He returned to Newfoundland as assistant superintendent of Roman Catholic schools.
[1] After being elected in 1919, he was offered the position of Minister of Agriculture but declined and sat in opposition.
MacDonnell's health declined soon after he returned to farming and he died in St. John's the following year.