The earliest days of Catholicism in the Camden Diocese date back to the Salem County area where Mass was offered in the 1740's. The Salem missions were interupted by the Revolutionary War and abandoned until 1847 when Father William O'Hara, pastor of St. Patrick's, Philadelphia and later Bishop of Scranton, came to Salem and offered Mass on March 17, 1847, in the house of Matthew McBride, located at the corner of Broad and Second Streets. Father O'Hara made regular pastoral visits to Salem, and then in May 1848 Father Edward Waldron of Gloucester was appointed to attend the Salem area. In December 1851, St. Mary's was erected as a parish with Father John McDermott as the first resident pastor. The church at Salem was dedicated on July 4, 1852.