St. Mary's parish was founded in 1880.[2] What would become the Diocese of Fargo was established nine years later as the Diocese of Jamestown, and at the time it encompassed the entire state of North Dakota.[3]St. James Church in Jamestown became the cathedral.[4] The diocese's first bishop, John Shanley, moved his residence to the Island Park area of Fargo in 1891. The Holy See changed the name of the diocese to Fargo in 1897.[5]
Bishop Shanley purchased property for a new cathedral and had plans created. The basement was completed when a fire destroyed most of downtown Fargo in 1893. Shanley donated a large portion of the funds that he had personally raised for the new cathedral to reconstruct the city after the fire. Construction on the cathedral was, therefore, delayed. St. Mary's Cathedral was completed and it was dedicated on May 30, 1899.[3]