Diocese of Dallas, Texas Sep 242009 Also known as Dioecesis Dallasensis Diocese of Dallas-Fort Worth Founded 15 July 1890 by Pope Leo XIII Suffragan of Archdiocese of San Antonio, Texas Bishops Additional Information Catholic-Hierarchy.Org Diocese of Dallas Google Map Patron Saints of the Diocese Notes Father Joseph Martinere (later vicar-general) ministered there for many years before the diocese was established.