Local builder James Hardie (c. 1806–1889) constructed this Gothic Revival church from the design of Baltimore architect Long. An 1850 New York auction catalog included Long’s original drawings for a “Natchz [ sic] Cathedral,” and St. Mary closely resembles Long’s St. Alphonsus Church (1841–1845) in Baltimore. Bishop John Chanche came to Natchez from Baltimore and apparently used Long for both churches.
The exterior was largely complete by the mid-1840s, but an economic depression delayed St. Mary’s completion. Lawsuits filed by unpaid craftsmen and suppliers provide detailed information about the church’s construction. In 1859, a newspaper article described the newly finished interior as Perpendicular Gothic and identified Irish immigrant Warner (1797–1876) as the architect and builder who completed the work.
The leaded and stained glass memorial windows and the Stations of the Cross date to the 1880s and 1890s. The Conrad Schmitt Studios of Wisconsin installed the Carrara marble altar rail, screens, and bishop throne in 1930 and later oversaw an elaborate renovation and repainting of the interior after a storm in 1998. St. Mary’s was designated a minor basilica in 1999. Just south is the Greek Revival Rectory (1846–1847) by Natchez builder John Crothers.