ordained to the priesthood for the Archdiocese of Chicago by Archbishop Patrick Feehan on June 24, 1887.[3] Dunne furthered his studies at the Pontifical Gregorian University in Rome, obtaining a Doctor of Divinity degree in 1890.[2] After returning to Chicago, he received his first pastoral assignment at St. Columbkille Parish in Chicago, where he remained for eight years.[2] He was later named pastor of Guardian Angels Parish and chancellor of the archdiocese.[2]
Bishop of Peoria
On June 30, 1909, Dunne was appointed as the second bishop of the Diocese of Peoria by
During the early 1920s, the future Archbishop Fulton Sheen, a popular television host in the 1950s, was a priest in the diocese. After spending time in pastoral and teaching jobs in the United Kingdom, Dunne told Sheen to return to Peoria in 1925. Both Columbia University in New York and Oxford University in England offered him teaching positions. However, instead of allowing Sheen to take one of these prestigious position, Dunne assigned him as a curate to St. Patrick's, a poor parish in Peoria. Sheen took the assignment without any complaints and enjoyed his time there.[4] Nine months later, Dunne summoned Sheen to his office. Dunne told him:
I promised you to Catholic University over a year ago. They told me that with all your traipsing around Europe, you'd be so high hat you couldn't take orders. But Father Cullen says you've been a good boy at St. Patrick's. So run along to Washington.[4]