Born June 18, 1855 in Pittsburgh, Pennsylvania, he was the son of John O’Connor and Mary Connelly. His father was named as one of the first benefactors of the Passionist Congregation in the United States. After initial education in local Catholic Pittsburgh schools he went to St. Vincent’s College, Latrobe, Pennsylvania. There he began to entertain thoughts about the priesthood so he made a retreat at St. Paul of the Cross Passionist Monastery in Pittsburgh. After discussion with Father Anthony Calandri, C.P., O’Connor applied to enter the Passionists. He professed his vows on July 4, 1876. Studies before ordination were at the Passionist foundations at Cincinnati, Ohio, and Dunkirk, New York. While at Dunkirk his health began to fail and he was required to leave class for a length of time. He gained strength by studying music. During an annual community retreat he had the opportunity to reflect again with Father Calandri who was residing at Dunkirk. Father Calandri urged the young O’Connor that proficiency in music would make him more susceptible to the realities of the secular world. This led the aspiring Passionist priest to destroy a large portion of his secular sheet music. Rarely throughout the rest of his life did he play the piano.
In 1878 Father John Dominic Tartalinni was elected Consultor General of the Congregation and six United States students accompanied him to Rome. O’Connor was one of them. Students were studying at the International College of the Congregation which was set up at Scala Sancta. O’Connor and others studied philosophy at Sts. John and Paul Monastery in Rome. Health took its toll. Two students at Sts. John and Paul developed tuberculosis and returned to the United States. O’Connor remained in a weak condition. On June 11, 1881 he was ordained to the priesthood.
Still, as he was finishing studies his health did not improve and he was sent, with two lay-brothers, to the Passionist foundation in Naples, Italy. No improvement was shown and it was deemed necessary to have him stay in Italy with two of his companion students rather than go back to the United States. Later, when the United States superiors were on their way back home, Father O’Connor, against the will of the Superior General who thought O’Connor would die at sea, finally went home. The fears of the Superior General were almost realized. Father O’Connor had to be carried off the ship. Finally, back in the United States he was able to regain his strength and after several months made it back to Pittsburgh.
In 1887 the Preparatory Seminary was established at St. Mary’s Dunkirk. Father O’Connor, a member of the Community at the time divided his duties. On the one hand he was assisting as Director of Students; on the other hand he was ministering to Catholics in nearby Forestville, New York. In 1888 he was transferred to Louisville, Kentucky to take charge of a class of students for one year. In 1889 he was involved in parish work at Holy Cross Church, Cincinnati. Later, he came to St. Michael’s Monastery in West Hoboken, New Jersey.
At St. Michael’s he began to minister to inmates of Hudson County at Snake Hill. Located there were the county Penitentiary, the Alms House, County Hospital for Consumptives, the Insane Asylum, the Pest House and Orphaned Children. Father O’Connor became one with the people of Snake Hill. He fought for their rights against officials who tried to suppress those rights. With the help of friends, Father O’Connor was able to erect a prison chapel at Snake Hill. For several years he lived with these people enduring much of the same food and lodging especially as they suffered from small-pox. Finally in 1915 his health was so broken that it was considered essential that he take leave of the ministry so he went to Pittsburgh for several months. However, upon return to St. Michael’s in West Hoboken he did not go back to Snake Hill. Instead he ministered at the monastery. At 62 years of age he looked like 80. Worn out he died in 1916.