Dr. O'Connor was born in Clonea on Christmas Day 1848. He had only one brother who was also a priest. He was educated by the Christian Brothers in Dungarvan and at 'All Hallows', where he was ordained for Armidale, New South Wales, Australia, on 15 September 1875. O'Connor sailed for Australia on St. Patrick's day 1876.

In 1882 he was made Dean and Vicar General, and in May 1903 he was appointed Bishop of Armidale. According to a newspaper edition he was described as 'a young man...who is a fine specimen of the Irish type of athlete, being about 6ft. Tall and weighing about 200 lbs...well built, with a fine head, well poised on a pair of broad shoulders; his unassuming, kindly manner wins everyone.' Some time afterwards Dr. O'Connor returned home on a visit. His aunt Mother Mary Francis was Superior of the Presentation nuns in Lismore at that time. From Ireland he set sail for New York and then on to San Francisco from where he travelled to Honolulu, New Zealand and finally Australia. He was held in high regard by both Catholics and Protestants. Dr. O'Connor died in Armidale in 1929.