Archdiocese of New Orleans, Louisiana Sep 162009 Founded 25 April 1793 by Pope Pius VI as the Diocese of Louisiana and the Two Floridas Elevated 19 July 1850 to an Archdiocese by Pope Blessed Pius IX Suffragans Bishops Additional Information Archdiocese of New Orleans Catholic-Hierarchy.Org Patron Saints of the Archdiocese Notes Name changed to the Diocese of New Orleans on 18 July 1826.